JP2001097436A - Packaging container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable water vapor produced in a container to be efficiently discharged out of it when it is heated by a microwave oven or the like and enable surrounding atmosphere to be efficiently fed into it when a pressure within the container is reduced upon completion of heating operation in the case of the packaging container for storing a lunch or various kinds of cooked foods or the like, for example, and in particular, the container in which its circumferential edges of its main body and a lid are fitted to each other and sealingly closed. SOLUTION: This container is comprised of a substantial rectangular container main body thermally molded by a synthetic resin sheet and a lid 2 and this is a full- circumference fitted packaging container in which an aeration feature and a water passing feature between inside part and outside portions of it when its lid is completely applied to the container can be substantially shielded. A fitted state at its corner is partially released with pressure of water vapor generated inside the container is heated by a microwave oven so as to generate the aeration passage and at the same time the generated water vapor is discharged out of the container and thereafter its heating is terminated and so even if a temperature within the container is lowered, the container is not sealingly closed again automatically by the lid and then air reverse flowed into the container through the aeration passage can be taken into it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging container for use, for example, for storing a bento or various kinds of cooked foods, and more particularly to a container having a container body and a lid, and the periphery of the container body and the lid. The present invention relates to a packaging container in which parts are fitted to each other and hermetically sealed.

[0002]

2. Description of the Related Art Conventionally, for example, when the above-mentioned cooked foods are displayed and sold, they are hermetically contained in a packaging container comprising a container body and a lid, and when the foods are eaten, the whole container is used electronically. Heating is performed in a microwave oven or the like.

[0003] The packaging container used for the above-mentioned applications not only ensures a sufficient hermeticity so that liquid sap and the like of the food contained in the container do not leak outside, and also uses a microwave oven or the like. When the steam is generated by heating, the container is excessively expanded, and the steam is efficiently released out of the container so as not to be ruptured. The container must not collapse under atmospheric pressure.

Therefore, conventionally, by forming a hole or notch communicating with the inside and outside of the container on the upper surface of the lid, water vapor can be released during heating, and outside air can be introduced from the hole or notch during depressurization. This has been proposed (see, for example, Japanese Utility Model Application Laid-Open No. 63-180555).

[0005]

However, in the case where a hole or cut is formed in the lid as described above, when the food contained in the container contains a liquid such as a boiled liquid or a sauce,
When transported by truck or the like, displayed at a store, or carried by a purchaser, there is a risk that liquid juice may leak out from the drilled holes or cuts, and garbage or dust may enter.

In order to solve the above-mentioned problems, for example, it is conceivable to wrap the entire container with a wrap or the like. However, the juice leaking from the above-mentioned hole or notch seeps out between the wrap and the container. There is a risk of damaging the appearance or soiling the surroundings.

[0007] Further, after heating in a microwave oven or the like, when decompression occurs in the container due to cooling, the wrap blocks the holes and cuts, so that outside air cannot flow into the container. There was a problem that the container body and the lid were crushed.

[0008] The present invention has been proposed in view of the above-mentioned problems, and does not provide holes or cuts in the lid as in the conventional case described above, and removes steam generated when heated by a microwave oven or the like outside the container. It is an object of the present invention to provide a packaging container which can discharge the air into the container well when the heating is completed and a reduced pressure is generated in the container.

[0009]

In order to achieve the above object, a packaging container according to the present invention has the following constitution.

That is, a substantially rectangular container body and a lid thermoformed from a synthetic resin sheet, and a full-peripheral fitting that can substantially block air permeability and water permeability between the inside and outside of the container when completely covered. This is a type of packaging container, in which the corners are partially released due to the pressure of water vapor generated inside the container when heated in a microwave oven or the like to create a ventilation path, and the generated water vapor is discharged to the outside. Even if the temperature inside the container is reduced by releasing and then heating is stopped, the outside air can be taken into the container through the ventilation path without the container being resealed by the lid naturally. And

More specifically, for example, the fitting portion formed on the peripheral edge of the container body and the fitting portion formed on the peripheral edge of the lid body are pressed against each other so as not to cause leakage of liquid juice when the lid is covered. In the case of a container having a structure in which the fitting structure is formed so as to be in close contact with each other and the lid body is fitted inside and outside of the container body, the upper portion of the inside of the fitting portion at the corner of the container body does not reach the lowermost portion of the fitting portion. A ventilation recess is provided, or a ventilation recess which does not reach the top of the fitting portion is provided at the lower side of the fitting portion at the corner of the lid, and the fitting at one or both corner positions of the container body and the lid is performed. The purpose can be achieved by forming a ventilation path forming concave or convex part in the joint part.

In the case of a container having a structure in which the lid fits inside the container body, a concave portion that does not reach the lowermost part of the fitting portion is provided on the upper side inside the fitting portion at the corner of the container body, or the lid body is provided. The purpose can be achieved by providing a concave portion which does not reach the uppermost portion of the fitting portion at the lower side inside the fitting portion of the corner portion.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a packaging container according to the present invention will be specifically described based on an embodiment shown in the drawings. FIG. 1 is a plan view showing an embodiment of a packaging container according to the present invention, FIG. 2 is a front view showing a state in which a lid is opened, FIG. 3 (a) is an enlarged sectional view taken along line AA in FIG. (B) is the same figure in the state where the lid was fitted to the container main body, and FIG. 4 is an enlarged perspective view of the corner part of the container main body.

The illustrated packaging container comprises a container body 1 and a lid 2, each of which is formed into a substantially rectangular box shape by vacuum forming a transparent synthetic resin sheet. The material of the synthetic resin sheet is not particularly limited as long as it does not significantly deform due to high-temperature steam heated in a microwave oven. Specifically, for example, polypropylene or heat-resistant polystyrene resin is used alone. Alternatively, a material obtained by laminating them, a material obtained by blending an inorganic filler or an organic filler with a resin, or a foamed material can also be used. In particular, as the container body, a polypropylene resin excellent in cost and heat resistance, oil resistance and other practicality, or a compound containing an inorganic filler such as talc is suitable,
The most suitable material for the lid is a polypropylene resin having good transparency, heat resistance, oil resistance and the like.

At the periphery of the container body 1 and the lid 2,
Fitting portions 11 and 12 each having a U-shaped cross section whose lower surfaces are open.
1 are formed, and by fitting them together, an inner / outer fitting structure is formed in which the inner surface side and the outer surface side of the fitting portions 11 and 21 are closely fitted to each other, whereby the inside of the container is almost completely sealed. It is configured to be.

The fitting portions 11 and 21 are provided over the entire periphery of the container body 1 and the lid 2 each having a substantially rectangular planar shape, and are provided at four corners (hereinafter referred to as corners).
Is formed in an arc shape. Upper surface (upper piece) 1 of U-shaped fitting portion 11 of container main body 1 at the arc-shaped corner portion
FIG. 4 shows a corner portion between the inner surface 1a and the inner surface (inner piece) 11b.
As shown in FIGS. 1 and 3, an inclined surface 11s forming the ventilation recess S is formed on the outer surface (outer piece) of the U-shaped fitting portion 21 of the lid 2 at the corner portion as shown in FIGS. Is provided with a convex portion 21t that forms a ventilation path T between itself and the fitting portion 21 of the container body 1. The protrusion 21t is formed in a semi-cylindrical shape in the illustrated example, but the shape is appropriate.

In the present embodiment, the convex portions 21t are provided at different positions at the left and right corners as shown in FIG. If the left and right directions are sequentially changed when stacking a plurality of lids by this, it is possible to overlap with a predetermined interval maintained by the convex portion 21t, and the adjacent lids are firmly fitted. The separation can be prevented from becoming difficult.

Fitting portions 11 and 12 between container body 1 and lid 2
It is desirable that the first and second containers 1 and 2 are tightly fitted to each other to prevent leakage of the liquid juice. In this embodiment, the lower part of the fitting part 11 of the container body 1 is located at the lower part of the fitting part 21 of the lid. Are so-called under-processed so that they are pressed against each other. That is, the lower part of the fitting part 21 of the lid is formed slightly narrower than the upper part, and when the fitting part 11 of the container body 1 is fitted, the lower part of the fitting part 21 of the lid slightly spreads. While being fitted to the lower part of the fitting part 11 of the container body 1, it is configured to be elastically pressed against the lower part by the elastic restoring force and hermetically sealed.

In the above configuration, when, for example, food is accommodated in the container body 1 and the lid 2 is covered, and the fitting portions 11 and 21 of the container body 1 and the lid 2 are fitted, the inside of the container becomes almost completely. Since the container is hermetically sealed, even if food containing a large amount of liquid juice or water is placed and laid, the liquid juice or water does not leak to the outside.

In this state, when the container is heated with a microwave oven, the liquid juice, water, and the like in the container become steam and fill the container, and the internal pressure gradually increases. When the pressure rises to a predetermined value, one of the four corners is usually released by the internal pressure and a part of the lid 2 is lifted up. The water vapor in the container is discharged out of the container through the inclined portion 11s, the gap between the upper surfaces 11a and 21a of the fitting portions 11 and 21, the inner space of the semi-circular convex portion 21t, and the like. This lid 2
Is lifted and the fittings 11 and 21 at one corner are disengaged due to the increased pressure in the container and occur at a stretch, so that the ventilation recess is provided between the container body 1 and the lid 2. A sufficient air passage for releasing the water vapor in the container to the outside, including the inclined portion 11s constituting S and the convex portion 21t constituting the ventilation path T, is secured.

In this state, the lid 2 is provided with the U-shaped fitting portion of the lid 2 near both ends S1 of the concave portion S, that is, near both circumferential ends of the inclined surface 11s of the container body 1 shown in FIG. 2
Since the lower portions of the inner pieces 21b and 21c are kept on, the container and the inside of the container are gradually cooled after the heating by the microwave oven, and the above-mentioned condition is applied even when a negative pressure is generated in the container. Air can flow into the container from the air passage. Thereby, the container can be prevented from being deformed or crushed. After sufficient air has flowed into the container, the fitting portion 1 between the container body 1 and the lid 2
If the fingers 1, 2 are picked up from both upper and lower sides with fingers or the like and refitted, they can be sealed again.

Although not shown in the drawing, even when the container is wrapped in a wrap or the like, the lid 2 floats up and releases water vapor in the container in the same manner as described above when heated by a microwave oven. The wrap is softened by the released high-temperature water vapor, and the wrap contains an anti-fogging agent. A gap is created, and air can be sucked in even after the end of heating.

In the above embodiment, the outer surface 2 of the fitting portion 21 of the lid 2 is used as a means for forming the ventilation path T.
1c is formed with a convex portion 21t.
A concave portion may be formed on the outer surface 11c of the first member, or both the concave portion and the convex portion 21t may be provided.

In the above embodiment, the container body 1
And the lid 2 are hermetically fitted by fitting portions 11 and 21 having a U-shaped cross section formed on their peripheral edges. However, as shown in FIG. May simply be internally fitted. FIG. 6A shows the container body 1.
FIG. 1B is a cross-sectional view of a corner portion in a state where the lid body 2 is fitted to the above, and FIG. The same operation and effect as in the embodiment of FIG. 5 can be obtained. The fitting portion 11 of the container main body 1 and the lid 2 in FIG. 6 has a U-shaped cross section as in the above embodiment, but the upper surface 11a of the U-shaped fitting portion 11 is shown in FIG. It may be configured to extend flat outward as indicated by a chain line.

In the above-described embodiment, the slope 11s forming the ventilation recess S is formed in the fitting portion 11 of the container body 1. For example, as shown in FIG. 21 may have an inclined portion 21s. The inclined part 2
1s may be formed in accordance with the above-mentioned inclined portion 11s,
In this case, the above-mentioned press contact portion may be provided above the fitting portions 11 and 21. 7 (b), the lid 2 may be so-called internally fitted to the container body 1, and the upper surface 11a of the U-shaped fitting portion 11 of the container body 1 may be externally fitted as shown by a chain line in FIG. It may be configured to extend flat to the side.

Further, in the above embodiment, as a means for forming the ventilation recess S, the inclined surface 11s is formed in the fitting portion of the container body 1 or the lid 2, but, for example, FIG. ), Or a rectangular recess 11 as shown in FIG.
By forming q and the like, the concave portion S for ventilation can be formed.

The above-mentioned vent recess S is formed by the viscosity of the air flowing into the container even if the corner of the lid 2 opened by the steam pressure as described above approaches the container body 1 after the heating is completed. The body 2 is retracted and provided in order to secure a gap so that the suction port is not closed by airtight fitting, and the vicinity of both ends of the concave portion provided in the container body 1 or the cover 2 is a cover or This purpose is achieved by supporting the lid with a gap in contact with the corresponding part of the container body.

Therefore, if the width of the concave portion is too large, the support is insufficient and it is difficult to secure a gap between the container body and the lid, and the lid is easily pulled in when inhaling air. If the size is too small, the gap between the container body and the lid is narrowed, so that it is difficult to obtain a necessary air flow path, and similarly, the lid is easily pulled in. Therefore, the width, shape, size, etc. of the above-mentioned concave portions are changed by the size of the container, the radius of the corner portion, and the softness of the material used or the change in softness due to heat, so the most appropriate degree is appropriately confirmed by experiments and the like. Must be provided.

As described above, the corners of the lid 2 are disengaged by the pressure of the water vapor, and the corresponding corners of the lid 2 are lifted, so that the water vapor is conveyed to the outside. It is an air passage for dissipating water vapor when it is released to the air, and a ventilation passage for air intake when air flows in from the outside after the end of heating.
Therefore, it is necessary to change the gap of the ventilation path depending on the size of the container.

[0030]

As described above, the packaging container according to the present invention is configured as described above, and has the following effects.

That is, since the container according to the present invention does not have a hole or a cut in the upper part of the lid as in the conventional case, it is possible to completely prevent foreign substances and dust from entering the container, and Even if foods or liquids containing a lot of juice are stored and transported or displayed, there is no leakage of juice due to the good sealing performance when the lid is covered. Furthermore, even when heating in a microwave oven, a vapor passage is easily formed at the corner of the lid due to the generated steam pressure so that the steam can be dissipated, and the internal pressure is prevented from being increased and the container is prevented from being deformed. Can be. Furthermore,
The air released together with the water vapor at the time of heating can maintain the ventilation path even when the water is sucked into the container again due to the condensation of the water vapor due to the cooling of the container. And the lid can be prevented from being crushed. In addition, even when this container is further wrapped in wrap, the lid is lifted up, and high-temperature steam comes out of the air passage, so that the wrap becomes soft, and a defogging agent is added to the wrap. Since the wrap is wet and condensed with water, the folded wrap has a ventilation gap communicating with the outside, so that air can be sucked in even after the end of heating, and the inside of the container can be prevented from decompressing and crushing the container. .

Further, since a series of effects as described above can be obtained, the container according to the present invention can be used very easily as a container containing a large amount of water and sap, which can be heated in a microwave oven. Since the crushing phenomenon of the container due to the internal decompression does not occur, the appearance and the commercial value are not degraded.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a packaging container according to the present invention.

FIG. 2 is a front view showing a state where a lid of the packaging container is opened.

FIG. 3A is an enlarged sectional view taken along line AA in FIG.
(B) is the same figure in the state where the lid was fitted to the container main body.

FIG. 4 is an enlarged perspective view of a corner of a container body in the packaging container.

FIG. 5 is a cross-sectional view of a corner portion in a state of being heated by a microwave oven or the like.

FIG. 6 is a cross-sectional view of a corner portion showing a modified example of a fitting portion between a container body and a lid.

FIG. 7 is a sectional view of a corner portion showing another modified example of the fitting portion between the container body and the lid.

FIG. 8 is a perspective view of a corner portion showing a modified example of the concave portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container main body 2 Lid body 11, 21 Fitting part 11s, 21s Inclined part 21t Convex part S Vent part T Vent path

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E084 AA05 AA14 AA24 AA26 AB10 BA01 CA03 CC03 CC05 DA03 DC03 DC05 FA09 FC03 FC07 GA08 GB12 KA02 4B055 AA10 AA17 BA07 BA13 CA06 CA21 CA73 CB03 CB08 CC43 FA01 FB35 FC12

Claims (4)

[Claims] 1. A container having a substantially rectangular container body thermoformed from a synthetic resin sheet and a lid, and which can substantially block air permeability and water permeability between the inside and outside of the container when completely covered. A container for packaging, wherein the pressure of water vapor generated inside the container when heated in a microwave oven partially releases the fitting of the corners to create a ventilation path and release the generated water vapor to the outside, Even if the temperature inside the container is lowered by stopping heating after that, the air flowing back into the container through the ventilation path can be taken in without the container being resealed by the lid naturally even if the temperature inside the container decreases. Packaging containers. 2. A packaging container having a structure in which a lid fits inside and outside of a container body, wherein a vent recess not reaching the lowermost portion of the fitting portion is provided at a corner position of the inner fitting portion on the container body side. Or, at the corner position on the lid side, a ventilation recess that does not reach the uppermost portion of the fitting portion is provided, and a projection for forming a ventilation path on the container body side or the lid side or both at the corner position of the outer fitting portion. 2. The packaging container according to claim 1, wherein a portion or a concave portion is provided. 3. A packaging container having a structure in which a lid fits inside a container body, wherein a venting recess that does not reach the lowermost portion of the fitting portion is provided at a corner position of the fitting portion on the container body side. And a ventilation recess which does not reach the uppermost portion of the fitting portion is provided at a corner position on the lid side.
The container for packaging according to the above. 4. The packaging container according to claim 1, wherein the sealing release portion of the lid due to the pressure of the steam can be resealed by pushing the lid into the main container side.