JPH0659892B2 - A notch forming device for the collar of a food packaging container - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a notch forming device for a collar portion of a container used for packaging desserts, cooked foods and the like.

2. Description of the Related Art Conventionally, for example, an aluminum foil and a film layer of two or more layers bonded to the upper surface of the aluminum foil and having a first surface side
A laminated sheet consisting of a synthetic resin film whose film layer has an easy peel (easy peeling) adhesive strength,
Containers for food packaging that are provided with a container body formed by drawing a synthetic resin film on the inside and a collar portion provided at the peripheral edge of the opening of the container body are already known, and The first film layer on the surface side of the flange portion of the container is provided with an annular notch for peeling around the flange portion, and the heat provided on the lower surface of the first film layer portion and the lid outside the notch. The sealing material layer and the sealing material layer are heat-welded to seal the container, and when the container is opened, the grip is provided on the lid and when the lid is peeled off, the first film layer of the container collar portion and the heat of the lid are heated. Until the sealing material layer was joined, the first film having a weak adhesive strength was peeled off from the next layer, easy peeling was possible, and the opening was extremely easy.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, according to such a conventional food packaging container, the depth of the cut is adjusted, and the protruding length of the piston rod of the upper die lifting cylinder having the cut forming blade is adjusted. However, it is very difficult to adjust the depth of the cut, and therefore it is not possible to stably form the cut having a predetermined depth.

Therefore, when the cut is too shallow and the first film layer is not cut, the lid is unsealed, and when the cut is too deep and the synthetic resin film layer is completely cut and the cut reaches the aluminum foil, the collar portion However, there was a problem in that the strength of the

The object of the present invention is to solve the above-mentioned problems of the prior art, the depth of the cut to be formed in the collar portion of the food packaging container, depending on the thickness of the collar portion and the thickness of the synthetic resin film, It can be adjusted very easily and reliably, it is possible to stably form a notch having a predetermined depth, and the strength of the flange is high, and the storage performance of the contents is remarkably excellent. Moreover, various food packaging containers that are easy to open are
It is an object of the present invention to provide a notch forming device for a collar portion of a food packaging container, which can be produced very efficiently and can be supplied to the market at low cost.

Means for Solving the Problems This invention is, in order to achieve the above object, a collar portion of a food packaging container, a device for forming an annular cut around the collar portion, the container body in the central portion. A lower die having a container body accommodating portion to be fitted therein and having an annular step portion at a peripheral portion, and an annular cut facing the collar portion placed on the upper surface of the lower die around the container body accommodating portion and projecting downward. An upper die having a forming blade and having a downward annular convex portion on a peripheral edge thereof, an annular upper die receiving member arranged in an annular step portion of the lower die and receiving the downward annular convex portion of the upper die, and an upper die receiver A gist of the present invention is a device for forming a notch in a collar portion of a food packaging container, which comprises at least one annular notch depth adjusting plate interposed between a member and a lower annular step.

For example, a food packaging container used for packaging desserts, cooked foods, and the like is generally a laminated sheet made of an aluminum foil and a synthetic resin film bonded to the upper surface of the aluminum foil, with the synthetic resin film inside. It is provided with a container body formed by drawing and a collar portion provided on the peripheral edge of the opening of the container body.

In the above, as the aluminum foil, for example, 40 to
The one having a thickness of 200 μm is used.

Further, as the synthetic resin that constitutes the synthetic resin film,
For example polypropylene, polyethylene, polyester,
Examples thereof include synthetic resins such as polyvinyl chloride and polycarbonate. The synthetic resin film has a total thickness of 20
It is 0 to 400 μm, preferably 250 to 350 μm.

In addition, recently, a synthetic resin having an aluminum foil and two or more film layers joined to the upper surface of the aluminum foil, and the first film layer on the front surface side having an easy peel (easy peeling) adhesive strength A laminated sheet made of a film is often used for a food packaging container having a container body formed by drawing a synthetic resin film as an inner side and a flange portion provided at an opening peripheral portion of the container body. There is. In this case, the thickness of the synthetic resin film is
200-400 μm as a whole, preferably 250-3
The thickness is 50 μm, and the same synthetic resin as described above is used as the synthetic resin forming each film layer.

Here, a specific example of the synthetic resin film is an unstretched coextruded film composed of two layers of polypropylene and high-density polyethylene. In this case, the peel strength of both layers is 500 to 1500 g / 15 mm width, preferably 70
The width is 0 to 900 g / 15 mm. Of course, the coextruded film may be a combination of other two synthetic resin film layers, or may have three or more film layers.

Further, the synthetic resin film may be a film in which two or more film layers are bonded to each other via an adhesive layer instead of the above-mentioned coextruded film. Between the first film layer and the next second film layer, an easily peelable adhesive layer such as a polyether adhesive is interposed, or an ordinary adhesive such as a urethane adhesive is used. By interposing an adhesive layer and an easily peelable coating layer such as a silicone-based paint, the first film layer is bonded to the second film layer with the bonding strength as described above, and the first film layer can be peeled It is what has been made.

Further, for joining the aluminum foil and the synthetic resin film, for example, an ordinary adhesive such as urethane adhesive, polyester adhesive and maleated polypropylene, or an ionomer, that is, a monoolefin-unsaturated carboxylic acid copolymer is used. An adhesive composed of a resin or a metal salt thereof (see, for example, Japanese Patent Publication No. 61-54587) is appropriately used depending on the type of synthetic resin film to be adhered.

A printing layer is usually provided on the outer surface of the aluminum foil via an adhesive layer, and a protective coating layer is further provided on the outer side of the printing layer. The outermost protective coating layer is for protecting the aluminum foil, which is excellent in chemical resistance, weather resistance and the like epoxy resin, nitrocellulose resin, polyethylene phthalate, unstretched polypropylene,
It is composed of nylon and the like.

The notch forming device according to the present invention, in the collar portion of the food packaging container, in forming an annular notch around the collar portion, in order to adjust the depth of the notch, an annular upper die receiving member, and At least one annular cut depth adjusting plate is interposed between the mold and the annular stepped portion.

Therefore, for example, the total thickness of the collar portion of the food packaging container is 500
In the case of μm, the height of the upper circular cut forming blade is the same as the height of the downward annular convex portion, and the height of the upper die receiving member is the same as the height from the upper surface of the lower die to the annular step. The thickness of the annular cut depth adjusting plate to 2
If it is set to be 00 μm and is interposed between the upper die receiving member and the annular stepped portion, an upper die annular cut forming blade can always form a 300 μm deep incision in the flange portion of the container. Is.

Embodiment Next, an embodiment of the present invention will be described based on the drawings.

The food packaging container (10) comprises a 100 μm thick aluminum foil (2) and a 300 μm thick unstretched coextruded synthetic resin film bonded to one side of the aluminum foil (2) via an adhesive layer (4).
As shown in FIG. 2, the laminated sheet (1) consisting of (3) and the unstretched coextruded synthetic resin film (3) are placed inside, as shown in FIG. That is, it comprises a container body (11) formed by drawing and forming with a depth / aperture of about 3/4, and a collar portion (12) provided on the peripheral edge of the opening.

The unstretched co-extruded synthetic resin film (3) comprises a first film layer (3a) made of high-density polyethylene and having a thickness of 70 μm on the surface side, and a 230 μm-thick film made of polypropylene on the aluminum foil (2) side. It has two film layers (3b), and the first film layer (3a) is releasably adhered to the second film layer (3b) with an adhesive strength of about 800 g / 15 mm width.

The device of the present invention is an annular cut that cuts the first film layer (3a) on the surface side of the collar portion (12) of such a food packaging container (10) and surrounds the collar portion (12). An apparatus for forming (16), the details of which are shown in FIG.

That is, the device of the present invention has a container body accommodating portion (23) in which the container body (11) is fitted in the central portion, and a lower mold (21) having an annular step portion (24) in the peripheral portion, and a container. Main unit housing
(23) has a circular notch forming blade (25) that protrudes downward and faces the flange (12) placed on the upper surface (21a) of the lower die (21) around the periphery of the lower mold (21) Convex part (2
An upper die (22) having a 6) and an annular upper die receiving member (27) arranged on the annular step (24) of the lower die (21) and receiving the downward annular convex portion (26) of the upper die (22). ), The upper die receiving member (27) and the lower die (21)
And at least one annular cut depth adjusting plate (28) interposed between the annular step portions (24).

Here, the upper die (22) has a heater on the bottom surface of the die holder (30).
It is attached via the block (31), and the heater block (31) has a built-in heater (32) corresponding to the annular cut forming blade (25) of the upper die (22). . Die
The holder (30) is designed to move up and down by inserting and removing the piston rods of a pair of lifting hydraulic cylinders (33), and the heater block (31) is attached to the bottom surface of the die holder (30). The upper mold (22) is attached to the lower surface of the heater block (31) by bolts (34), respectively, by bolts (35).

In FIG. 5 above, the height (A) of the downward annular convex portion (26) of the upper die (22) and the height (B) of the annular notch forming blade (25) are the same, and the upper die receiving member is the same. Height (C) of (27) and lower mold (21) and upper surface
The height (D) from the (21a) to the annular step (24) is made the same, and the thickness of the annular cut depth adjusting plate (28) is set to 200 μm, which is set to the upper die receiving member (27). ) And annular step
And (24).

And prepare 100 of the food packaging containers (10),
These containers (10) are successively placed in the lower die (21) container body housing (23)
, Heater temperature 200 ℃, pressure 1kg /
By heating and pressurizing for 1 second under the condition of cm ² , the flange portion (12) of each container (10) has an annular V-shaped cross section around the flange portion (12) as shown in FIG. Notches (16) were formed.

The total thickness of the collar portion (12) of each container (10) is 400 μm,
As a result of the above test, the collar portion (12) of all containers (10)
Cuts (16) having a depth of 200 μm ± 10 μm were formed, and the cuts (16) of each container (10) showed almost no variation in the depth in the circumferential direction.

In this embodiment, the depth of the cuts (16) of the collar portion (12) of each container (10) is 200 μm ± 10 μm, and therefore the cuts (16) extend to the second film layer (3b). However, the cut line (16) is not limited to this and may be any cut line that cuts at least the first film layer (3a).

As shown in FIG. 4, the contents (not shown) such as desserts and cooked foods are stored in the food packaging container (10) obtained as described above, and then heat-sealed on the lower surface. Timber layer (1
The lid (13) having 4) is covered, and the first film layer (3a) portion outside the cut line (16) and the heat-sealing material layer (14) of the lid (13) are heat-sealed. An opening knob (15) is provided on one side of the peripheral edge of the lid (13).

In this embodiment, the collar portion (12) of the food packaging container (10).
Cuts (16) for cutting the first film layer (3a) to be formed on
The depth of the cut can be adjusted very easily and reliably by setting the thickness of the annular cut depth adjusting plate (28) to stabilize the cut (16) having a predetermined depth. It can be formed by.

Thus, for example, the cuts (16) are too shallow and the first film layer (3a)
There is no possibility that the lid (13) will be unsealed without being cut, and the cut (16) is too deep to cut the synthetic resin film layer (3), and the cut (16) is made of aluminum. Foil (2)
There is no concern that the aluminum foil (2) will be corroded by the contents of the container (10), the durability will be deteriorated, and the strength of the collar portion (12) will be reduced.

In the heat-sealed state in this manner, when the pulling tab (15) for opening the lid (13) is pulled upward, the unstretched coextruded film is obtained.
About 800g / 15m between two film layers (3a) and (3b) of (3)
Since it is adhered in a state that it is easy to separate with an adhesive strength of m width, as shown by the chain double-dashed line in the figure, the cut (16) of the first film layer (3a) on the surface side of the coextrusion film (3) The outer side portion is easily peeled off from the second film layer (3b) while being joined to the heat-sealing material layer (14) of the lid (13), and easy peeling is possible.

In the above embodiment, the cross section of the cut line (16) is V-shaped, but the cross section shape of the cut line (16) is not limited to this and is arbitrary.

Also shown is a cut line (16) for cutting the first film layer (3a) at a portion of the collar portion (12) near the peripheral edge of the container body opening.
Is provided over substantially the entire circumference of the collar portion (12), but such cuts (16) may be provided in the container body opening peripheral edge portion of the collar portion (12) itself.

Further, the illustrated annular cut (16) is continuous over the entire circumference of the flange (12), but after heat sealing, it is easy to peel off the portion outside the cut (16) of the first film layer (3a). In that case, the annular cut (16) may be, of course, discontinuous so-called perforation.

EFFECT OF THE INVENTION The present invention, as described above, in the collar portion of the food packaging container,
A device for forming an annular cut around a collar part, which has a container body accommodating portion into which a container body fits in a central portion, and a lower die having an annular step portion at a peripheral portion, and a container body accommodating portion. Arranged on the upper mold having an annular cut forming blade that faces the collar part placed on the upper surface of the lower mold and protrudes downward, and has a downward annular convex part on the peripheral edge, and the annular step part of the lower mold. And an annular upper die receiving member for receiving the downward annular convex portion of the upper die, and at least one annular notch depth adjusting plate interposed between the upper die receiving member and the lower annular step portion. Therefore, the depth of cuts to be formed in the collar of the food packaging container can be adjusted very easily and reliably by appropriately setting the thickness of the annular cut depth adjusting plate. , Cut with a certain depth Eye in which it is possible to stably form.

Therefore, for example, the cut is too shallow and the first film layer is not cut so that the lid does not open undesirably. Further, the cut is too deep and the synthetic resin film layer is cut, and the cut is made of aluminum foil. There is no worry that the strength of the collar part will decrease after reaching to.

In addition, prepare various cut adjustment plates with different thicknesses, and replace or stack two or more of these plates according to the thickness of the flange of the food packaging container and the thickness of the synthetic resin film. This makes it possible to adjust the depth of cuts to be formed in the collar portion very easily and surely, and thus, the storage performance of the contents is remarkably excellent, and various food packaging containers that are easy to open are provided. It has an effect that it can be produced very efficiently and can be supplied to the market at low cost.

[Brief description of drawings]

1 is a partially enlarged sectional view of a laminated sheet constituting a food packaging container, FIG. 2 is a schematic sectional view of a food packaging container, and FIG.
The drawing is an enlarged cross-sectional view of the main part of the container of FIG. 2 with a lid, which is taken along line III-III in FIG. FIG. 4 is a schematic perspective view of the container with a lid, and FIG. 5 is a schematic cross-sectional view of a notch forming device of a collar portion of a food packaging container according to the present invention. (1) …… laminated sheet, (2) …… aluminum foil, (3) ……
Synthetic resin film, (3a) ... First film layer, (3b) ...
… Second film layer, (4) …… Adhesive layer, (10) …… Food packaging container, (11) …… Container body, (12) …… Flange part, (13) ……
Lid, (14) …… Heat-sealing material layer, (21) …… Lower mold, (21a) …… Lower mold upper surface, (22) …… Upper mold, (23) …… Container body accommodating section, (24)
…… Annular step, (25) …… Annular cut forming blade, (26) ……
Downward annular projection, (27) …… Upper die receiving member, (28) …… Cutting depth adjustment plate.

Claims (1)

[Claims] 1. A collar portion (1) on a collar portion (12) of a food packaging container (10).
A device for forming an annular cut (16) around 2),
Container body accommodating part (23) in which the container body (11) fits in the central part
And a lower mold having an annular step (24) on the periphery.
(21) and a peripheral notch forming blade (25) facing the collar portion (12) placed on the upper surface (21a) of the lower mold (21) around the container body accommodating portion (23) and projecting downward. And an upper die (22) having a downward annular convex portion (26) on the peripheral portion, and a lower die (2
An annular upper die receiving member (27) disposed on the annular stepped portion (24) of (1) and receiving the downward annular convex portion (26) of the upper die (22), an upper die receiving member (27) and a lower die ( 21) An apparatus for forming a notch in a collar portion of a food packaging container, comprising at least one annular notch depth adjusting plate (28) interposed between the annular step portions (24).