JP2571569B2 - Easy-open sealed container with drop lid for container - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an easily-openable sealed container using a dropping lid for a container. More specifically, the present invention is suitable for use in packaging containers for foods, particularly for a liquid food packaging container, and can be strongly heat-sealed to a container, has high pressure resistance against pressure from the inside of the container, and has excellent sealing properties. ,
In addition, the present invention relates to an easily-openable sealed container using a dropping lid for a container having excellent opening-peelability.

[Conventional technology]

BACKGROUND ART Conventionally, packaging by filling a container body with an article and then heat-sealing a lid material to the periphery of an opening of the container body is often used for packaging various foods. Above all, packaging using a lid material with a falling lid time, instead of a general film-shaped lid material, can reduce the residual air in the container and improve the preservability of food. Therefore, it is widely used for packaging of liquid foods such as soft drinks, soups, jellies, and creams.

However, in this packaging form, when filling the container with contents such as soup and setting the dropping lid, the contents overflow into the flange portion of the container, and the content drops and prevents heat sealing of the lid and the container flange portion, In some cases, the sealing strength required for the sealing property to withstand the external force during transportation or the internal pressure during retort may not be obtained. Therefore, when the temperature and pressure of the heat seal are increased to increase the seal strength in order to obtain a sufficient sealing property, it is difficult to open the lid and the easy-opening property is impaired. As a means to achieve both sealing and easy-opening, instead of peeling the lid between the heat-sealed lid and the flange of the container, the lid has a multilayer structure,
Although the lid is opened by peeling off the upper layer of the lid while leaving a part of the lower layer of the lid heat-sealed to the container flange part in the flange part, a conventionally known structure is used. Thus, when retort treatment or the like is performed, it is not possible to achieve both the sealing property and the easy-opening property that can withstand the high internal pressure applied from the inside of the container body.

[Problems to be solved by the invention]

The present invention solves these problems, has excellent sealing properties, and has good peeling-opening properties at the time of use, and provides an easy-opening sealed container using a dropping lid for containers having strong sealing properties and easy-opening properties. It is something to offer.

[Means for solving the problem]

That is, the present invention provides an easy-opening property in which a container dropping lid having an annular easily peelable resin layer on the heat-sealing surface to the container body is annularly heat-sealed to the opening flange of the container body filled with the contents. In a hermetically sealed container, heat sealing is performed so that the inner end of the annular easily peelable resin layer is located on the flange inside the inner end of the annularly heat sealed heat seal portion, and the outer peripheral portion of the container drop lid and the container body The present invention provides an easily-openable sealed container characterized in that an inner peripheral portion of the container is closely attached to the container.

 Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of one embodiment of a container drop cover and a container body for heat-sealing the same according to the present invention. (1, 2)
Is a multilayer drop lid, 1 is an outer layer of the lid material, and 2 is an inner layer of the lid material.
3 is a container main body. Reference numeral 4 denotes a flange portion, which is filled with the contents and covered with a multilayer dropping lid, and the container body 3 and the multilayer lid material are tightly heat-sealed by the flange portion 4 in a ring shape. Reference numeral 5 denotes an annular cut, which forms an annular easily peelable resin layer 7 on the drop lid. FIG. 3 is an enlarged partial cross-sectional view showing a state in which the opening flange portion of the container main body is covered with a dropping lid. As shown in the figure, the flange inside the inner end 9 of the heat seal portion 8 which is heat-sealed annularly. Heat sealing is performed such that the inner end (cut 5) of the annular easily peelable resin layer 7 comes to the upper side. When heat sealing is performed in this manner, the outer peripheral portion 11 of the container drop lid and the inner peripheral portion 12 of the container main body are in close contact with each other even when internal pressure from the inside of the container main body is applied to some extent, such as in the case of retort processing, and easy peeling on the flange Since the inner end (cut 5) of the permeable resin layer 7 is not exposed to the internal pressure, the inner end (cut 5) of the easily peelable resin layer
Moreover, even if a gap is generated in the adhered portion due to internal pressure, internal pressure is applied to the non-heat-sealed portion 10 of the easily peelable resin layer, and the inner end of the easily peelable resin layer (notch) The easily peelable resin layer from 5) does not easily peel off, and as a result, it is very difficult to open the container against internal pressure from inside the container body. The width not heat-sealed, that is, the distance between the inner end of the annular heat seal portion, the inner end 9 of the easily peelable resin, and the inner end 5 of the easily peelable resin layer is 0.5 to 5 mm. preferable.

Here, the adhesive strength between the flange portion of the container body and the easily peelable resin layer of the dropping lid needs to have difficulty in peeling, and the interlayer peeling strength is usually 2.0 kg / 15 mm or more (tensile speed 30 mm / min. And the same hereinafter), preferably 2.3 kg / 15 mm or more. On the other hand, the interlayer adhesion between the drop lid and the easily peelable resin layer needs to be smaller than the adhesive strength between the flange portion of the container body and the easily peelable resin layer of the drop lid, and the interlayer peel strength is usually 1.5 kg / 15mm or less, preferably 1.3k
g / 500g / 15mm is desirable.

 Reference numeral 6 denotes a knob for facilitating opening.

FIG. 2 is a cross-sectional view showing a state where the multilayer dropping lid is peeled off from the container in which the container dropping lid and the container body of FIG. 1 are heat-sealed. After peeling has occurred between the outer layer of the lid material of the drop lid and the easily peelable resin layer, the inner layer of the drop lid is cut at the notch 5, and the drop lid is peeled off. The easily peelable resin layer remains in a state fused to the flange portion 4 of the container body.

The outer edge of the flange portion of the container body of the easily-openable sealed container of the present invention may have ribs or curls for enhancing strength, synthesis, usability, and the like. Since the easily openable sealed container of the present invention is opened by delamination between the drop lid and the easily peelable resin layer at the time of opening, even if these reinforcing members are provided, the drop lid is easily peeled off similarly to a container having a flat flange. can do.

In the present invention, when a multilayer dropping lid is used, the cut 5 provided in the inner layer of the lid material is for cutting the inner layer in the flange surface when peeling the multilayer dropping lid, and is usually provided as an annular cut. Any material that can easily cut the inner layer of the multi-layer drop cover when peeling the multi-layer drop cover may be used. Even if the layer in contact with the inner layer (the outer layer in the case of a two-layer structure) is cut, a part of the inner layer is removed. Only may be cut. In addition, the cut may be provided in a ring, such as a circle, a triangle, or a square, depending on the shape of the container, so that the inner periphery of the flange may be provided over the entire circumference, or a part thereof may be left. In the case where the multilayer dropping lid is opened without leaving a part of the lid, the cut is not made only in the part that is not peeled off.

The notches can be formed by pressing the heated ring, pressing the ring (blade), ultrasonic processing, cutting with a cutting blade, laser processing, or by shearing. ,
Or a combination of these.

The shape of the recess of the drop lid of the present invention is not particularly limited as long as the air can be expelled by fitting into the opening of the container body, and may be a curved shape, a shape having a flat bottom surface, or the like. Further, as a method of forming the drop lid, thermoforming such as vacuum forming and pressure forming, press forming and the like are used.

The shape of the container body of the easily-openable sealed container of the present invention is not particularly limited, but is usually a circle, a square, or the like,
It is heat-sealed with the container drop lid in an annular shape along the flange portion of this shape. It may be cup-shaped or tray-shaped.

Although the multi-layer drop lids (1, 2) have a two-layer structure in FIG. 1, they may have either a two-layer structure or a multi-layer structure of two or more layers. Of a container body made of polyethylene, polypropylene, ethylene-α-olefin copolymer, ethylene-vinyl acetate copolymer, or the like, and a base material (outer layer) made of multi-layer plastic, paper, aluminum foil, or a composite material thereof. What consists of an inner layer and a sealant layer (inner layer) made of a resin having easy heat sealing properties is preferably used.

When the cuts are formed by a heating means such as a hot blade, the material of the outer layer preferably has a higher melting point and softening point than the material of the inner layer so as not to impair the shape of the multilayer lid member. For example, the material of the inner layer is preferably a polyethylene resin, and the material of the outer layer is preferably paper, aluminum foil, a heat-resistant resin such as polypropylene, nylon, polyester, or polycarbonate, or a resin containing an inorganic filler.

In addition, in the easily-openable sealed container of the present invention, as long as it has the feature of the present invention having the easily-peelable resin layer, the inside of the easily-peelable resin layer or the container body may include other components such as a seal layer as necessary. May be provided.

The method for forming the easily peelable resin layer of the present invention includes (1)
A method of forming a notch by using a multilayer material such as a multilayer film as described above, (2) A method of dropping a seal film having a hole equal to the opening of a container in advance and attaching the film to a lid base material, (3) Heat A method of heat sealing by putting a holed seal film between the drop lid base material and the container body at the time of sealing. (4) Heating by putting a donut-shaped sealing material between the drop lid base material and the container body at the time of heat sealing. There are a method of sealing, (5) a method of welding a ring-shaped resin to the drop lid base material, and the like.

In the method (1) of forming using a multilayer material, a resin film, paper, an aluminum foil, and other base materials are further combined by co-extrusion using the above-mentioned combination of resins having releasability, and laminated. A multilayer material is obtained by processing, coating, or the like, and a notch is formed in the multilayer drop lid obtained from the multilayer material by the above-described method to form an easily peelable resin layer on the drop lid. This method is preferable because it is easy to manufacture.

The container body in the easily-openable sealed container of the present invention is not limited by its material, layer structure, manufacturing method, etc., and is strongly heat-sealed to the easily peelable resin layer of the drop lid at the flange portion of the container. The heat sealing method is not limited at all.

When the material of the container body is a resin, as the resin, polyolefin resin, polystyrene resin, polyamide resin, polyester resin, ethylene-vinyl alcohol copolymer, polyacrylonitrile, polyvinylidene chloride resin, inorganic filler There is a resin mixed with 5 to 70% by weight, or a mixture thereof. If necessary, a thermoplastic elastomer, a modified polyolefin modified with an unsaturated carboxylic acid or a derivative thereof, or the like is used for these resins, and a resin mixed with various additives is used.

These resins are formed into a single-layer or multi-layer container body by sheet thermoforming, injection molding, blow molding, injection blow molding, or the like.

The material of the container body may be paper or metal, or a composite container of these and resin. These composite containers are formed into containers by bonding, winding and the like.

In any case, as a normal container body, a container body having an inner layer of a dropping lid and an inner layer of a container body which is easily heat-sealed and has a strong adhesive force is used. The shape of the container body is not limited, and may be a cup shape or a tray shape.

[Action]

When the container drop lid of the present invention is used for the container body after filling the contents and the multi-layer drop lid is heat-sealed, the easily openable sealed container can be easily opened by the following operation.

For example, in FIG. 2, that is, when the portion 6 is lifted upward, delamination starts between the inner layer 2 and the outer layer 1 of the multilayer drop lid at the outer end of the easily peelable resin layer 7 and the multilayer drop lid reaches the cut 5. Delamination progresses and cuts 5
At this point, the inner layer of the multilayer drop lid is cut, and the multilayer drop lid is peeled off. The easy-openability of the present invention in a sealed container,
Even if the peel strength of the heat seal is increased, the peelability between the layers of the multi-layer dropping lid is not impaired, and as a result, an easily openable sealed container having a stable opening force is obtained. In addition, even if the overflowing contents are attached to the heat seal part at the time of drop lid setting, it is possible to increase the temperature, pressure, etc. at the time of heat seal,
High sealing performance can be obtained.

Further, the multi-layer dropping lid can be peeled regardless of the shape of the container body, such as with a rib or curl.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples.
The present invention is not limited in any way by these examples.

Example 1 A container body with a flange (60 mmφ, × 40 mmH) was obtained from a high-density polyethylene sheet by air pressure molding. The inner layer is high-density polyethylene and the outer layer is polypropylene
A drop lid as shown in FIG. 1 formed of a mixed resin layer of 80% by weight and 20% by weight of low-density polyethylene and having a cut 5 formed inside the heat-sealed portion with a heating blade was heat-sealed.

When the dropping lid was peeled off from the container formed in this way, it was peeled off between the layers of the lid material of the multi-layer dropping lid, and then the inner layer of the lid material was cut off at the cut, so that it could be easily opened, and the opening force was also stable. I was

〔The invention's effect〕

Advantageous Effects of Invention According to the present invention, an easily-openable sealed container having excellent properties such as high sealing strength, excellent sealing properties, easy opening even when the container has ribs and the like, and stable opening force is obtained. I was able to. In addition, in the conventional container, both the hard peeling property and the easy peeling property were required on the heat sealing surface, whereas in the easily openable sealing container of the present invention, the heat sealing face and the peeling face were different, By simply providing a heat-sealable resin layer as the inner layer of the drop lid, in selecting the material of the container body, it is sufficient to consider the heat-sealability with the easily peelable resin layer, and the selection range of the material is expanded. The practical value is extremely large.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an embodiment of a drop lid and a container body of the present invention, and FIG. 2 is a cross-sectional view showing a state in which a sealed packaging container in which the drop lid and the container body of FIG. 1 are heat-sealed is opened. . FIG. 3 is an enlarged partial cross-sectional view showing a state in which the lid has been dropped on the opening flange of the container body and the lid has been heat-sealed. In the drawing, reference numerals (1 and 2) denote a multilayer drop lid, 1 denotes a multilayer lid material outer layer, 2 denotes a multilayer lid material inner layer, 3 denotes a container body, 4 denotes a flange portion, 5 denotes a cut, 6 denotes a block portion, and 7 denotes an easily peelable portion. 8 is a heat seal portion, 9 is an inner end of the heat seal portion, 10 is a portion of the easily peelable resin layer that is not heat sealed, 11 is an outer peripheral portion of a container drop lid, and 12 is an inner peripheral portion of a container body. is there.

Claims (1)

(57) [Claims] 1. An easy-open property in which a container dropping lid having a ring-shaped easily peelable resin layer on a heat-sealing surface to a container body is heat-sealed annularly to an opening flange of the container body filled with contents. In a hermetically sealed container, heat sealing is performed so that the inner end of the annular easily peelable resin layer is located on the flange inside the inner end of the annularly heat sealed heat seal portion, and the outer peripheral portion of the container drop lid and the container body An easily openable hermetically sealed container, characterized in that the inner peripheral portion of the container is in close contact with the inner peripheral portion of the container.