JPH0720004Y2 - A notch forming device for the collar of a food packaging container - Google Patents

Description

TECHNICAL FIELD The present invention relates to a notch forming device for a collar portion of a food packaging container used for packaging desserts, cooked foods and the like.

Conventional Technology Conventionally, as shown in FIG. 5, for example, aluminum foil (4
A synthetic resin film layer (42), which is bonded to the upper surface of the synthetic resin film layer (42) with an adhesive strength of easy peeling (easy peeling), is formed by drawing with the synthetic resin film layer (42) inside. A container for food packaging (50) including a container body (51) formed by the above and a flange portion (52) provided at the peripheral edge of the opening is already known, and the flange of the container (50) is known. Part (52) synthetic resin film layer (42)
An annular peeling notch (notch) (43) surrounding the collar portion (52) was provided by a notch forming device (57) having an annular notch forming blade (58) protruding downward.

However, depending on the shape of the notch forming blade (54), the synthetic resin film layers (42) on both sides of the notch (43) are conventionally used.
The raised portions (44) (44) are formed in the portions, and the container collar portion (5) having such raised portions (44) (44) is formed.
2), the heat-sealing material layer (54) is formed on the lower surface as shown in FIG.
A heat-sealing device (56) to heat-weld the film layer portion outside the cut line (43) and the corresponding heat-sealing material layer portion on the lower surface of the lid to the container (50). )
Not only is heat-welded to the film layer portion and the heat sealing material layer portion outside the cut line (43), but also the raised portions (44) of the synthetic resin film layer (42) on both sides of the cut line (43). (44) and the heat-sealing material layer (54) are joined, and there is a problem that the container (50) cannot be opened neatly when the opening knob (55) of the lid (53) is pulled and pulled upward. It was

The object of the present invention is to solve the above-mentioned problems of the prior art, and to form the cut stably in the synthetic resin film layer of the collar portion of the food packaging container with very little resin swelling. Provide a notch forming device for the collar portion of a food packaging container that can supply the market with a high quality food packaging container that does not cause defective opening even if the lid and lid of the food hermetically sealed are heated and welded. There is to try.

Means for Solving the Problems In order to achieve the above object, the present invention provides a lower mold having a container body accommodating portion at a central portion into which a container body of a food packaging container fits, and a periphery of the container body accommodating portion. In the upper mold having an annular notch forming blade that protrudes downward and faces the collar part placed on the upper surface of the lower mold, and the synthetic resin film layer of the collar part of the food packaging container has a collar part. In an apparatus for forming a circular cut in a circle, an upper die is attached to a lower surface of a vertically movable die holder via a heater block, and an annular step portion is provided on a peripheral portion of the lower die, and the upper die A downward annular convex portion is provided on the peripheral portion, and an annular upper die receiving member is arranged between the annular step portion and the downward annular convex portion, and the annular upper die receiving member and the lower annular step portion At least one annular kerf depth in between An adjusting plate is interposed, and the upper die for forming an annular cut is
It has a substantially trapezoidal cross-section that tapers gradually downward, and the length of the lower side is 50 to 150 μm, the angle between the two hypotenuses is 5 to 25 °, and the height is 3 to 5 mm. In addition, a notch forming device for the collar portion of the food packaging container is required.

The food packaging container is generally formed by drawing a laminated sheet made of an aluminum foil and a synthetic resin film joined to the upper surface of the aluminum foil in an easy peelable manner, with the synthetic resin film inside, and a container. It has a main body and a collar.

Here, as the aluminum foil, for example, 40 to 200 μm
Use one with a thickness of.

Further, as the synthetic resin forming the synthetic resin film layer,
For example polypropylene, polyethylene, polyester,
Examples thereof include synthetic resins such as polyvinyl chloride and polycarbonate. The total thickness of synthetic resin film is 200-4
It is 00 μm, preferably 250 to 350 μm.

In addition, recently, an aluminum foil is bonded to the upper surface of the aluminum foil with a normal adhesive and has two or more film layers, and the first film layer on the surface side is the next second film layer. On the other hand, a food packaging container formed by drawing a laminated sheet made of a multilayer synthetic resin film bonded with an adhesive strength capable of easy peeling in the same manner as described above is often used. In this case, the synthetic resin film layer has a total thickness of 200 to 400 μm, preferably
The thickness is 250 to 350 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 multilayer 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 500-1500g / 15mm width, preferably 700-900g / 15m
It is m wide. Of course, the coextruded film may be a combination of the other two synthetic resin film layers, and
You may have a film layer more than a layer.

Further, the multilayer synthetic resin film may be one in which two or more synthetic resin film layers are bonded to each other through an adhesive layer instead of the above-mentioned coextrusion film, and in this case, the surface Between the first film layer on the side 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. The first film layer is bonded to the second film layer with the bonding strength as described above by interposing the adhesive layer and the easily peelable coating layer such as a silicone-based paint, and the first film layer is peeled off. It is possible.

Further, the annular cut forming blade forms an annular cut around the collar portion in the synthetic resin film layer of the collar portion of the food packaging container (the first film layer on the surface side in the case of a multilayer synthetic resin film) And, as described above, it has a substantially trapezoidal cross section that tapers gradually downward, and the length of the lower side is 50 to 150 μm, and the angle between the two hypotenuses is 5 to 25 °. And the height is 3 to 5 mm.

Here, if the length of the lower side of the blade is less than 50 μm, the cut is sharp because the blade is thin, and therefore, the rise of the synthetic resin is small, but the blade edge is easily damaged. Again 150
If the thickness exceeds μm, the synthetic resin is largely raised, and unsealing failure is likely to occur in the container after the food is hermetically packaged. If the angle θ between the two hypotenuses of the blades is less than 5 °, the blades are thin and the blade edges are also easily damaged. On the other hand, if the angle exceeds 25 °, the synthetic resin will be largely raised, and unsealing will easily occur in the container after the food is hermetically packaged. If the height of the blade is less than 3 mm, the lower surface of the upper mold equipped with the heater approaches other parts of the synthetic resin film layer other than the planned cut formation part,
This is not preferable because the synthetic resin film layer may be distorted or the film layer portion may be melted. If the height of the blade exceeds 5 mm, the blade is likely to break, which is not preferable.

Embodiment Next, an embodiment of the present invention will be described with reference to the drawings.

The food packaging container (10) has a thickness of 10 as shown in FIG.
It consists of a 0μm aluminum foil (1) and a 300μm thick high density polyethylene resin film (2) that is peelably bonded to one side of this with an adhesive strength of about 800g / 15mm width via an adhesive layer. Laminate the resin film (2)
And a collar body (12) provided on the periphery of the opening of the container body (11) formed by drawing
It is composed of and.

The device of the present invention cuts a required portion of the synthetic resin film layer (2) of the collar portion (12) of the food packaging container (10) to form an annular cut (3) around the collar portion (12). ) Forming apparatus, the details of which are shown in FIGS. 1 and 2.

That is, the score forming device has a container body (11) at the center.
Lower mold (21) having a container body accommodating portion (23) into which
And an annular notch forming blade (25) projecting downward facing the flange (12) mounted on the upper surface (21a) of the lower mold (21) around the container body accommodating portion (23). The blade (25) for forming an annular notch has a substantially trapezoidal cross section that gradually tapers downward and has a lower side length (l) of 140 μm and two oblique sides. The angle (θ) between them is 22 ° and the height (H) is 3.5 mm.

An annular step (24) is provided on the peripheral edge of the lower mold (21), and a downward annular convex portion (26) is provided on the peripheral edge of the upper mold (22).
Is provided, an annular upper die receiving member (27) is disposed between the annular step portion (24) and the downward annular convex portion (26), and the annular upper die receiving member (27) and the lower die ( At least one annular cut depth adjusting plate (28) is interposed between the annular stepped portion (24) and the annular stepped portion (24).

Further, the upper die (22) is attached to the lower surface of the die holder (30) via the heater block (31), and the heater block (31) is for forming an annular cut of the upper die (22). A heater (32) is incorporated so as to face the blade (25). The die holder (30) is designed to be moved up and down by inserting and withdrawing the piston rods of a pair of lifting hydraulic cylinders (33), and the heater block (31) is mounted on the die holder (30). The upper die (22) is attached to the lower surface of the heater block (31) by bolts (35) on the lower surface and the bolt (34), respectively.

In FIG. 2 above, the downward ring-shaped convex portion (2
The height of 6) and the height of the circular cut forming blade (25) are the same, and the height of the upper die receiving member (27) and the upper surface (21a) of the lower die (21) to the annular step (24) The height is the same, and the thickness of the annular cut depth adjusting plate (28) is 300 μm, and the plate is interposed between the upper die receiving member (27) and the annular step (24).

Then, 10 of the food packaging containers (10) are prepared, and these containers (10) are sequentially fitted into the container body accommodating portion (23) of the lower mold (21), and the heater temperature is 200 ° C. and the pressure is 8 kg
By heating and pressurizing for 1 second under the condition of / cm ² , the flange (12) as shown in FIG. 1 is formed on the resin film layer (2) of the flange (12) of each container (10). An annular cut (3) having a V-shaped cross section was formed. At this time, raised portions having a height of about 100 μm were formed on both sides of the cut line (3).

Next, for comparison, with respect to an annular score forming blade having a substantially trapezoidal cross section which is gradually tapered downward, and the height (H) of which is 3.5 mm, the length of the lower side ( l) is 200 μm and the angle θ between the two hypotenuses is 2
A notch forming device provided with a blade having 2 ° (Comparative Example 1) and a lower side length (l) of 140 μm and an angle (θ) between two oblique sides of 30 ° (Comparative Example 2) was prepared. When a test was conducted in the same manner as in the above case, in Comparative Example 1, a raised portion having a height of about 500 μm was formed on both sides of the cut line (3), and in Comparative Example 2, on both sides of the cut line (3). A raised portion having a height of about 300 μm was formed.

Various food packaging containers (10) obtained as described above
After the contents (not shown) such as desserts and cooked foods are stored in the inside of the container, a lid (13) having a heat-sealing material layer (14) on the lower surface is covered as shown in FIG. (3) The resin film layer (2) portion on the outer side and the heat-sealing material layer (14) of the lid (13) are heat-sealed by the heat-sealing device (16). Holding the opening knob (15) of the lid (13) and pulling it upward, the resin film layer (2) and the aluminum foil (1) can be easily separated with an adhesive strength of about 800 g / 15 mm width. Since they are in close contact, the outer side of the cut (3) of the resin film layer (2) is peeled off from the aluminum foil (1) until it is joined to the heat sealing material layer (14) of the lid (13), In the embodiment of this invention, all 10 food packaging containers (10) could be opened without any problem. On the other hand, in the case of the food packaging container (10) of Comparative Example 1,
As a result of heat-sealing also the raised portions having a height of about 500 μm on both sides of the diced line (3) of the heat-sealing, the unsealing failure occurred in all 10 food packaging containers (10). Further, in Comparative Example 2, since there are raised portions having a height of about 300 μm on both sides of the cut line (3), 10 food packaging containers (1
Out of 3) containers (10) out of 0) had opening defects.

In addition, in the above-described embodiment, the notch (3) for cutting the resin film layer (2) is provided in the portion of the collar portion (12) near the peripheral edge of the container body opening over substantially the entire circumference of the collar portion (12). However, such a notch (3) has a collar part (12).
It may be provided on the periphery of the container body opening itself.

Further, the illustrated annular cut (3) is continuous over the entire circumference of the collar portion (12), but after heat sealing, the portion outside the cut (3) of the resin film layer (2) can be easily peeled off. If necessary, the annular cut (3) may of course be a discontinuous, so-called perforated shape.

Advantageous Effects of Invention The present invention, as described above, includes a lower mold having a container body accommodating portion into which a container body of a food packaging container is fitted, in a central portion,
A synthetic resin film of a collar portion of a food packaging container, and an upper die having an annular notch forming blade that protrudes downward and faces a collar portion placed on the upper surface of the lower die around the container body accommodating portion. In the layer, in the device for forming an annular cut around the collar, the upper-shaped annular cut forming blade has a substantially trapezoidal cross-section that gradually tapers downward,
The lower side has a length of 50 to 150 μm, the angle between the two hypotenuses is 5 to 25 °, and the height is 3 to 5 mm. It is used as a synthetic resin film layer on the collar of a food packaging container. It is possible to form stable cuts with very little resin swelling, and even if the flange and lid of a food hermetically sealed package are heated and welded, there will be no unsealing defects. The container can be supplied to the market.

The upper die is attached to the lower surface of the vertically movable die holder via a heater block, an annular step is provided on the peripheral edge of the lower die, and a downward annular convex portion is provided on the peripheral edge of the upper die. An annular upper die receiving member is provided between the annular step portion and the downward annular protruding portion, and at least one annular cut is provided between the annular upper die receiving member and the lower annular step portion. Since the depth adjusting plate is interposed, there is an effect that the depth of the annular cut can be adjusted accurately, easily and surely depending on the number of the adjusting plates arranged.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention.
The figure is a partially enlarged cross-sectional view of a food packaging container, showing a state in which cuts are formed by a cut forming device. Second
FIG. 3 is a schematic sectional view of a score forming device according to the present invention,
The figure is an enlarged cross-sectional view of a main part of the container shown in FIG. 1 with a lid, and shows a part of the heat sealing device. Fourth
FIG. 5 is a partially cutaway perspective view of a food packaging container with a lid, and FIG. 5 is a partially enlarged sectional view of a conventional food packaging container, showing a state in which a notch is formed by a notch forming device. FIG. 6 is an enlarged cross-sectional view of an essential part of the container shown in FIG. 5 with a lid, in which a part of the heat sealing device is shown. (1) ... Aluminum foil, (2) ... Synthetic resin film layer, (3) ... Notches, (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 section,
(25) ... Annular cut forming blade, (l) ... Length of cut forming blade lower side, (θ) ... Angle between two oblique sides of cut forming blade, (H) ... Cut forming blade Height of (26)
... Downward annular projection, (27) ... Annular upper die receiving member, (2
8)… Cutting depth adjustment plate, (30)… Die holder, (31)… Heater block.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Hasunuma 6-224 Kaiyamacho, Sakai City, Osaka Prefecture Showa Aluminum Co., Ltd. (56) Reference JP-A-63-150200 (JP, A) JP-A-63 -84921 (JP, A) Actual Kaihei 1-61004 (JP, U) Actual public Sho-57-41122 (JP, Y2)

Claims (1)

[Scope of utility model registration request] 1. A lower mold (21) having a container body accommodating portion (23) at a central portion into which a container body (11) of a food packaging container (10) fits, and a periphery of the container body accommodating portion (23). An upper die (22) having an annular cut forming blade (25) protruding downward and facing the collar portion (12) mounted on the upper surface (21a) of the lower die (21). In a device for forming an annular cut (3) around a collar (12) in a synthetic resin film layer (2) of a collar (12) of a container (10), a die in which an upper die (22) can be raised and lowered. -It is attached to the lower surface of the holder (30) via the heater block (31), the annular step (24) is provided on the peripheral edge of the lower die (21), and the peripheral edge of the upper die (22). Is provided with a downward annular convex portion (26), and an annular upper die receiving member (27) is arranged between the annular step portion (24) and the downward annular convex portion (26). In both cases, at least one annular cut depth adjusting plate (28) is interposed between the annular upper die receiving member (27) and the annular step (24) of the lower die (21), and the upper die ( The circular notch forming blade (25) of 22) has a substantially trapezoidal cross section that tapers gradually downward, and the length (l) of the lower side is 50 to 150 μm.
m, an incision forming device for a collar portion of a food packaging container, wherein an angle (θ) between the two hypotenuses is 5 to 25 ° and a height (H) is 3 to 5 mm.