JP2002249171A - Packing container for food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable disinfecting of a retort in the state where a food to be heated with a microwave oven is housed inside. SOLUTION: In this packing vessel consisting of a closed vessel main body 1 in which the food F to be heated with a microwave is housed inside and a lid body 10, the lid body is formed in a shape to be recessed downwards from connecting parts 2, 12 of the opening of the container main body to a lower part of the container main body so that the under surface 11 of the lid body reaches the top surface of the food in a non-filled state in the vessel as well as the bonding strength of the vessel main body and the like is characterized in setting so as to be peeled off with the increase in the internal pressure of the packing vessel by heating the food.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a food packaging container capable of performing retort sterilization in a state in which foods requiring heating by a microwave oven are housed therein.

[0002]

2. Description of the Related Art Conventionally, a food packaging container capable of performing retort sterilization in a state in which foods requiring heating by a microwave oven are housed therein generally has a plastic film formed in a bag shape.

[0003]

However, in the above-mentioned prior art, there is a problem in that the stored food must be transferred to a tableware after heating in a microwave oven. Then, it is very troublesome to take out the heated container by hand, open the container with a fingertip, and transfer the food, and there is also a problem that part of the food remains in the bag.

On the other hand, as shown in FIG. 5, there is known a container body 50 provided with a lid 51 as a packaging container which can be directly used as tableware. However, when retort sterilization is performed at high temperature and high pressure on this type of food in a container, there is a risk that the container may be deformed due to a change in atmospheric pressure. Therefore, no retort sterilization has been performed so far.

In the above case, the upper surface of the food F stored in the container body 50 and the lid 5
The presence of the air in the space A formed by the lower surface of the device 1 is exemplified. Therefore, if the space A is eliminated, the problem seems to be solved. However, this means that the container is full of food, and if it is assumed that the container will be used as it is as it is, it is clear from the fire that it will cause the food to spill around, The configuration could not be adopted. Further, when it is assumed that heating is performed in a microwave oven, there has been a problem that the internal pressure of the container rapidly increases due to generation of steam from the heated food and the container bursts.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and can be used as it is as a tableware, withstands retort sterilization, and can be heated in a microwave oven. It is intended to provide a container. That is, the food packaging container of the present invention is a packaging container comprising a container body and a lid which are sealed in a state in which the food required to be heated by the microwave is housed therein, and the food body contained in the container body in a non-full state. The lid is formed so as to be recessed downward from the joint of the opening of the container body so that the lower surface of the lid reaches the upper surface, and the joining force between the container body and the lid is formed by heating the food. It is characterized in that it is set to such a degree that it is peeled off by an increase in the internal pressure of the packaging container.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIGS. 1 and 2 are views showing a food packaging container (hereinafter, simply referred to as a “container”) of the present invention and a food container stored therein.
In the figure, reference numeral 1 denotes a container body, which is formed in a container shape with an open top, and a flange-shaped lid receiving portion 2 for supporting a lid described later is provided at the opening. It is assumed that the container body 1 has an appropriate rigidity. In this embodiment, the container body 1 is formed of a polyolefin-based plastic to be relatively thick.

[0008] In the figure, reference numeral 10 denotes a cover which is covered by the container body 1. The lid 10 has an annular main body joining portion 12 corresponding to the flange-shaped lid receiving portion 2 provided at the opening of the container main body 1 and has a shape recessed downward from the main body joining portion toward the lower side of the container main body. Be composed. That is, as shown in the drawing, the lid 10 is formed in a concave shape from the main body joint portion 12 to the lid lower surface 11, and when the lid is covered, the concave portion is just inside the container main body 1 like a middle lid. It will be fitted (see FIG. 2). In this embodiment, the lid 10
Is assumed to have flexibility, and in this embodiment, it is formed thin with a polyolefin-based plastic. The lid 10 may have a configuration that does not have flexibility, but in this case, an operation specific to this embodiment described later does not occur.

As shown in FIG. 2, the container body 1 and the lid 10 are covered with the food F after being stored in the container body. In this case, the lower surface of the covered lid is used. 11 is food F
The amount of the food and the dimensions of the lid are set so that the upper surface of the food does not reach the upper surface and no gap is formed between them.

When the lid is to be covered, the main body joining portion 12 of the lid 10 is joined to the lid receiving portion 2 of the container body 1 by the joining means X. The bonding force in this case is set to such an extent that the container is peeled off due to an increase in the internal pressure of the container due to the heating of the food, but the internal pressure of the container is from 300 g / cm ² to 500 g / cm.
As a result of the experiment, the applicant has come to know that it is effective to set the joining force so that peeling of each joint is started within the range of ² in order to achieve the effect of the present invention. That is,
If the peeling of the joint is started before the internal pressure of the package reaches 300 g / cm ² , it may be inadvertently opened at the time of distribution and handling, causing contamination of bacteria, and there is a risk of generating mold. In addition, when peeling is performed for the first time after exceeding 500 g / cm ² , high-pressure air is rapidly discharged to generate a popping sound, which gives the user a sense of unnecessary anxiety. In this embodiment as joining means X, employing heat sealing, by controlling the seal temperature and pressure have been set to be the bonding force within the range of 300 g / cm ² of 500 g / cm ^2, It goes without saying that the joining means is not limited to this.

[0011] When the container is made of plastic, the joining force weakens when heated. Therefore, the internal pressure of the container at the time of heating is 300 g / cm ² to 500 g / c.
When the bonding force is set so that the peeling of each bonding portion is started within the range of m ² , the value of the bonding force at a normal temperature where heating is not performed is higher.

According to the present invention, the container does not deform even when retort sterilization is performed under a high temperature and a high pressure in a state in which the food is accommodated therein. The reason is that the volume of a gas changes due to a change in pressure, but the volume of a liquid or solid such as stored food does not change. That is,
In the present invention, the lower surface 11 of the lid 10 is
Has reached, so there is no room for air in the container,
As a result, the above-described deformation does not occur.

On the other hand, when the food F is housed inside and heated by a microwave oven in a sealed state, the heated food F
However, in this embodiment, the lid 10 is flexible and has a shape recessed downward from the joint of the opening of the container body toward the lower part of the container body. The lower surface 11 is pushed upward due to the increase of the internal pressure because the pressure is increased, and the concave portion is first inverted and deformed into a convex shape protruding upward (see FIG. 3). As a result, a new space B is formed between the lower surface 11 of the lid 10 and the upper surface of the food F, and the internal pressure for pushing up the lid 10 is temporarily reduced. When the internal pressure increases again and reaches a preset value, the lid receiving portion 2 of the container body 1
The peeling of the lid 10 from the main body joint 12 is started, the sealing between the lid and the container body is released, and the steam is discharged to the outside to prevent the container from being ruptured.

In this embodiment, the edge-shaped rising portion 3 is further raised from the outer periphery of the lid receiving portion 2 of the container body 1.
In addition to the above, an edge-shaped rising portion 13 is provided further above the main body joining portion 12 of the lid 10 so as to correspond to this. This is based on the reason that a protective material such as a shrink film is covered on the upper surfaces of the edge-shaped rising portions 3 and 13 in the cover state to prepare for a pinhole trouble during distribution.

[0015]

The present invention having the above configuration has the following specific effects. Conventionally, there was a container that could use a plastic packaging container that can be heated in a microwave oven as it was, but there was nothing that could withstand retort sterilization, and the shelf life of the stored food was extremely short. According to the enabled food packaging container of the present invention, the expiration date of the food is drastically increased. As a result, it becomes possible to distribute soups, borschts, porridges, stews, and the like with the same convenience as cup ramen and the like, and wide demands such as foods for convenience stores, hospital meals, and nursing care meals can be expected. . Since the food is not full in the container, it does not spill when the user eats and contaminates the surroundings. The bonding strength between the container body and the lid is set to such a degree that the container is peeled off due to an increase in the internal pressure of the packaging container due to the heating of the food. In addition, since the food is not filled in the container, the food is not spilled into the microwave oven by the shock at the time of opening.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a food packaging container of the present invention.

FIG. 2 is a cross-sectional view of a state in which food is stored.

FIG. 3 is a cross-sectional view showing the same during heating.

FIG. 4 is a cross-sectional view showing a state in which the lid is removed.

FIG. 5 is a cross-sectional view of a state in which food is stored in a conventional food packaging container.

[Explanation of symbols]

 F Food X Joining means 1 Container body 10 Lid 11 Lower surface of lid

Claims (3)

[Claims] 1. A packaging container comprising a container body and a lid which are sealed in a state in which foods to be heated by a microwave oven are accommodated therein, wherein the lid body is provided on an upper surface of the food stored in a non-full state in the container body. The lid is formed so as to be recessed downward from the joint of the opening of the container body so as to reach the lower surface, and the joining force between the container body and the lid is reduced by the internal pressure of the packaging container due to the heating of the food. A food packaging container characterized in that it is set to such a degree that it is peeled off by rising. 2. The food packaging container according to claim 1, wherein the lid is flexible. 3. The internal pressure of the packaging container, which increases during heating, is 300.
g / cm claim 1 peeling of the joint has set the bonding force to be started from the ² in the range of 500 g / cm ² or 2 food packaging container according.