JP7262512B2 - Microwave container lid and microwave container - Google Patents

Description

TECHNICAL FIELD The present invention relates to a microwave oven-compatible container and its lid, in which food contained therein can be heated in a microwave oven with the lid closed.

In a packaging container of the type in which the main body and the lid are fitted together, when the contents such as food stored in the container are heated in a microwave oven, steam is generated when the contents are heated. It is necessary to eject. This is because if the generated water vapor cannot be adequately discharged, the pressure inside the container increases, causing problems such as the lid coming off from the container body.

Therefore, as a method for discharging the water vapor to the outside of the container, there is known a method of perforating the container with holes for ventilation or forming a ventilation path. On the other hand, depending on the size and size of the holes and air passages, there is a risk that dust, insects, etc. will enter, or foreign matter will be mixed in by mischief at the store.

In view of this, conventionally, there has been known a lid body that is used by being fitted to a container body, and has a recessed portion in the top surface portion thereof, and a long hole for exhaust is formed in the bottom surface portion of the recessed portion. (See Patent Document 1 below). However, if you put it in a flexible bag for carrying such as a bag or plastic shopping bag and carry it, if you put it on the loading platform or passenger seat of a car, motorcycle, bicycle, etc., or if you put it in a delivery service bag and transport it. However, it is difficult to keep the container body horizontal, and liquid from the contents may leak through the slot during transportation.

As means for preventing such liquid leakage, Patent Document 2 below discloses a lid body in which a long hole for exhaust is formed in the bottom surface of the recess and the entire recess is covered with a seal. However, when the recess is covered with a seal, liquid may leak into the recess through the slot and a large amount of liquid may accumulate in the space between the recess and the seal. When the liquid accumulated in this space comes into contact with the seal, the adhesive strength of the seal is lowered, and the seal is easily peeled off. Furthermore, since the seal portion comes into contact with the bottom surface of the stacked containers when the product is displayed or transported, there is a risk that the seal will inadvertently peel off and the liquid will leak out when the product is displayed at a store or carried after purchase. .

Japanese Patent No. 6538225 Japanese Patent No. 6830631

The present invention provides a microwave-safe container and its lid that can prevent foreign matter from entering the container during transportation and display, and can effectively prevent liquid leakage from the contents. The task is to

A microwave container lid according to the present invention is a food packaging container lid provided with a steam vent hole in the top surface portion and a seal for closing the steam vent hole, wherein the top surface portion includes: An uneven surface portion having a large number of uneven surfaces is provided, and steam vent holes are provided in the uneven surface portion.

According to this configuration, the contents are placed in the container and the container is covered with the lid. A seal is attached to the top surface of the lid, and the seal closes the steam vent hole. Therefore, the seal reliably prevents liquid from leaking from the contents during display or transportation. Also, the seal can prevent foreign matter such as insects from entering the container through the steam release hole. In the present invention, since the seal is adhered to the top surface of the lid with an appropriate strength, it is possible to completely prevent liquid leakage, and when the contents are heated with a microwave oven, the internal pressure rises to seal the contents. The inner pressure can be moderately maintained in a state in which the lid is not blown off while the steam in the container is released through the steam release hole, the steaming effect is obtained, and the cooking can be quickly performed. The top surface portion is provided with an uneven surface portion, and the uneven surface portion is provided with a steam release hole, and the seal is attached to the convex portion of the uneven surface portion. As a result, it is possible to prevent the seal adhesion surface from being damaged by the liquid that seeps out during transportation, etc., and the seal is reliably peeled off from the convex portion due to the selective increase in internal pressure during cooking. It is possible to prevent the lid jumping phenomenon.

In particular, it is preferable that the top surface portion is provided with a top surface recessed portion, the bottom surface portion of the top surface recessed portion is provided with an uneven surface portion, and the uneven surface portion is provided with a steam vent hole. According to this configuration, the uneven surface portion is provided on the bottom surface of the recessed top surface, and the steam vent hole is provided on the uneven surface portion of the bottom surface of the recessed top surface. It will be attached to the surface. Therefore, other objects are less likely to come into contact with the seal during transportation or display at the store. For example, when the containers are stacked one on top of the other, the top container is less likely to contact the seal of the bottom container. Therefore, the seal is not easily peeled off during transportation or display, and it is possible to reliably prevent contamination by foreign matter such as insects, and to reliably prevent liquid leakage.

Moreover, it is preferable that the convex portion of the uneven surface portion is a linearly extending ridge, and the steam vent hole is positioned in a gap between adjacent ridges or crosses the ridges. According to this configuration, the convex portion is reliably positioned adjacent to the steam vent hole. Therefore, the seal adhered to the convex portion can reliably prevent liquid leakage from the steam vent hole. is discharged outside the container.

Further, it is preferable that an annular protective wall protruding higher than the convex portion of the uneven surface portion is provided at the opening edge of the steam vent hole. According to this configuration, since the annular protective wall is provided at the opening edge of the steam vent hole, the seal is adhered to the protective wall in addition to the projections of the uneven surface. Therefore, the seal reliably prevents liquid leakage. Furthermore, since the protrusion height of the protection wall is higher than the protrusion height of the convex portion of the uneven surface portion, the seal is reliably adhered to the protection wall, and liquid leakage can be effectively prevented.

Further, the container for a microwave oven according to the present invention includes a container body and a lid fitted to the container body. The microwave oven container is attached to the top surface of the lid, and the top surface of the lid is provided with an uneven surface portion having a large number of uneven surfaces, and the uneven surface portion is provided with steam vent holes.

As described above, the seal adhered to the uneven surface can reliably prevent liquid from leaking from the vapor release hole, and can also reliably prevent foreign matter from entering the container. Moreover, since the seal is adhered to the uneven surface, the seal can be easily peeled off due to the increase in internal pressure caused by heating in the microwave oven, and the steam can be smoothly discharged to the outside of the container.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the lid open state of the container for microwave ovens in one Embodiment of this invention. The perspective view which shows the closed state of the same container. Fig. 3 is a cross-sectional view of a main part showing a closed state of the container; The partial enlarged plan view of the cover of the same container. AA end view of FIG. FIG. 6 is an end view corresponding to FIG. 5 showing a state where the lid is attached with a seal; FIG. 8 is an enlarged view of a main portion of FIG. 7; The partial enlarged plan view of the lid|cover of the container for microwave ovens in other embodiment of this invention. The partial enlarged plan view of the lid|cover of the container for microwave ovens in other embodiment of this invention. The partial enlarged plan view of the lid|cover of the container for microwave ovens in other embodiment of this invention. The partial enlarged plan view of the lid|cover of the container for microwave ovens in other embodiment of this invention.

Hereinafter, a microwave container and its lid according to an embodiment of the present invention will be described with reference to FIGS. 1 to 7. FIG. The container in this embodiment is for containing various foods, and is a microwave oven-compatible container that can be heated in a microwave oven with the lid closed without being opened. (ingredients) can be accommodated.

The container in this embodiment comprises a container body 1 and a lid 3 and further comprises an inner plate 2 . However, it may be one that does not include the inner plate 2 . A container provided with the inner plate 2 is suitable for use in which food is stored and sold in a vertically separated state. Although the same type of food may be vertically separated and stored, it is preferable to vertically separate and store different types of food.

The container body 1 has an opening that opens upward, and the lid 3 is fitted to the container body 1 to close the opening of the container body 1 . The fitting between the container body 1 and the lid 3 is preferably an internal fitting structure in which the fitting portion of the lid 3 is brought into contact with the inside of the fitting portion of the opening of the container body 1 and fitted. By adopting the inner fitting structure, it is possible to improve the sealing property so that the contained soup or the like does not leak when the lid is closed. In addition, as will be described later, the steam release hole 60 formed in the uneven surface portion 51 of the lid 3 is a fine hole, so that the internal pressure during cooking can be increased. By doing so, it is possible to prevent the cover from flying off, and to maintain an appropriate internal pressure, thereby improving the cooking efficiency. It is preferable that the inner plate 2 is also fitted inside the container body 1 .

The container body 1, the inner plate 2 and the lid 3 are all formed from a synthetic resin sheet by various thermoforming (sheet forming) such as vacuum forming and pressure forming. The container body 1 can accommodate a first food, and the inner plate 2 can accommodate a second food of a different kind from the first food. That is, by attaching the lid 3 to the container body 1, the container body 1 and the lid 3 form a compartmentalized storage space. is divided into an upper storage space on the upper side and a lower storage space on the lower side than the inner plate 2.例文帳に追加Therefore, the first food and the second food can be separately stored in the lower accommodation space (lower stage) and the upper accommodation space (upper stage).

For example, in the case of noodles, dashi stock or soup can be placed in the lower accommodation space, and noodles and ingredients can be placed in the upper accommodation space. Dashi and soup may be solidified with gelatin, or may be melted by heating in a microwave oven to become liquid. It is also suitable for hotpot dishes, and the lower storage space can be filled with dashi stock, and the upper storage space can be filled with ingredients. Although various kinds of foodstuffs may be used as described above, it is particularly suitable for storing foodstuffs containing moisture or liquids, especially foodstuffs containing a lot of moisture or liquids, which require high sealing performance.

The shape of the container in a plan view is arbitrary, and may be polygonal, elliptical, oval, oval, etc. in addition to round, but round is preferred. In the case of a polygon, each side may be linear or may be configured to bulge outward in an arc shape. Each corner may be arcuate, ie rounded.

The container main body 1 includes a main body bottom portion 10, a main body side portion 11 extending from the peripheral edge portion of the main body bottom portion 10 while expanding upward, and a main body flange portion extending outward from the upper end portion of the main body side portion 11. 12.

As shown in FIG. 3, the body side portion 11 is provided with a first body fitting portion 13 into which the lid 3 is fitted and a second body fitting portion 14 into which the inner plate 2 is fitted. is preferred. The shapes of the first main body fitting portion 13 and the second main body fitting portion 14 may be various, for example, a reverse tapered shape that tapers inward toward the upper side, or a vertical shape or forward tapered shape that tapers inward. It may have a shape provided with an inwardly fitting convex portion that protrudes. A stepped portion 15 may be provided between the first body fitting portion 13 and the second body fitting portion 14 . In the lid-closed state, the stepped portion 15 may be opposed to an intermediate plate flange portion 22 , which will be described later, and the lid horizontal portion 34 may be opposed to the intermediate plate flange portion 22 .

The body flange portion 12 may be provided with a knob portion (not shown) for facilitating the opening of the lid 3 . The body bottom portion 10 may be provided with legs (not shown) of various shapes. In the container body 1, jelly-like soup, noodles, scallops, etc. can be stored in advance so that they can be eaten by being heated as they are in a microwave oven. The container body 1 can be obtained by thermoforming a sheet using a heat-resistant resin material. Since the container body 1 is heated in a microwave oven and used, it is preferable to use a foamed heat-resistant resin material. The electromagnetic waves of the microwave oven can be efficiently transmitted to the stored foodstuffs, and the heating can be performed uniformly and in a short time. The container body 1 may be transparent, but is preferably made of a foam material having heat insulation properties.

<Middle plate 2>
The middle plate 2 includes a middle plate bottom portion 20, a middle plate side portion 21 extending upward from the periphery of the middle plate bottom portion 20, and a middle plate flange portion 22 extending outward from the upper end of the middle plate side portion 21. I have. The middle plate 2 is shallower than the container body 1 and is housed in the container body 1. - 特許庁The middle plate 2 is entirely inserted into the container main body 1, but in the housed state, the middle plate bottom portion 20 is in a state of floating upward from the main body bottom portion 10. - 特許庁Various ribs may be formed on the inner plate bottom surface portion 20 , and a continuous rib may be provided from the inner plate bottom surface portion 20 to the inner plate side surface portion 21 .

The inner plate 2 is preferably fitted inside the container body 1 . It is preferable that a middle plate fitting portion 23 that fits inside the second body fitting portion 14 of the container body 1 is provided on the upper portion of the middle plate side portion 21 . Although the shape of the middle plate fitting portion 23 may be various, for example, it may be a reverse tapered shape that tapers inward toward the top, or an inward fitting convex portion that protrudes inward in a vertical shape or a forward tapered shape. You may make it the provided shape.

The inner plate 2 is preferably provided with an internal communication portion for discharging the steam in the lower accommodation space to the upper accommodation space. The internal communication portion may have various configurations. For example, as shown in FIG. can be provided with a steam exhaust valve 25 . Incidentally, the steam discharge valve 25 may be provided at, for example, the central portion of the inner plate bottom portion 20 . Note that the internal communication portion may be a hole instead of a valve.

In order to prevent the so-called blocking phenomenon in which the middle plates 2 are tightly fitted to each other and cannot be removed when a large number of the middle plates 2 are stacked at the time of collection, the middle plate side portion 21 has a blocking prevention convex portion 27. may be provided. The anti-blocking protrusions 27 are arranged at different positions for each inner plate 2.例文帳に追加

The intermediate plate flange portion 22 may be provided with an intermediate plate knob portion 26 for allowing the intermediate plate 2 to be easily removed from the container body 1 . As shown in FIG. 2, the middle plate knob 26 may protrude to the outside of the container from the body flange 12 and the lid flange 32 when the lid is closed.

<Lid 3>
The lid 3 is preferably transparent so that the food contained in the container can be visually recognized from the outside through the lid 3 . The lid 3 includes a lid top surface portion 30 and a lid flange portion 32 located outside the lid top surface portion 30 . A lid fitting portion 33 that fits inside the first body fitting portion 13 of the container body 1 is preferably formed between the lid top surface portion 30 and the lid flange portion 32 . When the lid fitting portion 33 is provided, the lid flange portion 32 is formed outward from the lid fitting portion 33 . Further, it is preferable that a lid side surface portion 31 extends downward from the outer edge of the lid top surface portion 30 and a lid horizontal portion 34 extends substantially horizontally outward from the outer edge of the lid side surface portion 31 . In that case, it is preferable that the lid fitting portion 33 is formed upward from the outer edge of the lid horizontal portion 34 .

The lid fitting portion 33 may have various shapes. The lid fitting portion 33 may have, for example, a reverse tapered shape in which the upper side is inward, or may have a vertical shape or a forward tapered shape provided with an inward fitting convex portion that protrudes inward.

The lid flange portion 32 may be provided with a lid knob portion 35 for facilitating the lid opening operation. The lid side surface portion 31 is provided with an anti-blocking projection 36 to prevent a so-called blocking phenomenon in which the lids 3 are tightly fitted to each other and cannot be removed when a large number of the lids 3 are stacked at the time of collection. good. The anti-blocking protrusions 36 are arranged at different positions for each lid 3 .

It is preferable to form a stacking convex portion 37 on the periphery of the lid top surface portion 30 to prevent the containers from being displaced when the containers with the lids closed are vertically stacked. The stacking protrusion 37 protrudes upward. The stacking convex portion 37 may extend along the peripheral portion of the lid top surface portion 30 . A pair of stacking projections 37 may be formed. The pair of stacking protrusions 37 may be symmetrical to each other and may be formed at positions facing each other by 180 degrees.

The lid top surface portion 30 is provided with a first top surface recessed portion 41 and a second top surface recessed portion 42 that are recessed downward, that is, toward the inside of the container. However, the first top surface concave portion 41 and the second top surface concave portion 42 may not be provided. The shape, arrangement, size, etc. of the first top surface recessed portion 41 and the second top surface recessed portion 42 are arbitrary. The first top surface recessed portion 41 is larger than the second top surface recessed portion 42 . Also, the depth of the first top surface recessed portion 41 may be shallower than that of the second top surface recessed portion 42 . The direction in which the first top surface recessed portion 41 and the second top surface recessed portion 42 are aligned is referred to as the lid first direction, and the direction perpendicular to it in plan view is referred to as the lid second direction. 1, 2, 4, etc., the arrow X indicates the lid first direction, and the arrow Y indicates the lid second direction. FIG. 4 shows the first top surface concave portion 41 . The first top surface concave portion 41 may be, for example, substantially rectangular in plan view and elongated in the second lid direction. However, the first top surface concave portion 41 may be square, round, or the like.

With the lid closed as shown in FIG. 2, the belt-shaped label 5 printed with various information such as the name of the food is wound vertically from the top surface 30 of the lid 3 to the bottom surface 10 of the container body 1. preferably rotated. The pair of stacking projections 37 may be arranged to face each other in the lid second direction. Regions in which the stacking projections 37 are not formed may be provided at two locations facing the lid first direction in the peripheral edge portion of the lid top surface portion 30 . The belt-shaped label 5 is preferably wound so as to cover the first top surface concave portion 41, and is preferably wound along the lid first direction. The belt-shaped label 5 passes between the pair of stacking protrusions 37 and passes over two regions of the peripheral edge of the lid top surface portion 30 where the stacking protrusions 37 are not formed. An inclined surface may be provided at the boundary between the lid top surface portion 30 and the lid side surface portion 31 to facilitate the winding of the belt-shaped label 5 .

<Uneven surface portion 51>
The recessed bottom portion 50 of the first top surface recessed portion 41 may have a flat shape, a structure curved in one direction, or a dome shape having a peak on the content side, but the adhesive strength of the seal is uniform. From the point of view, it is preferably flat. As shown in FIGS. 4 to 7, an uneven surface portion 51 is provided on the recess bottom surface portion 50 of the first top surface recess portion 41 . The uneven surface portion 51 may be provided on the entire recess bottom surface portion 50 of the first top surface recess portion 41, or may be provided only on a part of the recess bottom surface portion 50 of the first top surface recess portion 41. Further, it may be provided on the entire lid top surface portion 30 of the lid 3, or may be provided on the entire lid 3, but in order to improve the appearance of the product, the sealing area should be made as small as possible. Therefore, it is desirable to reduce the area of the uneven surface portion 51 as much as possible.

In this embodiment, the concave-convex surface portion 51 is provided only on a portion of the recess bottom surface portion 50 of the first top surface recess portion 41 . The recessed bottom surface portion 50 of the first top surface recessed portion 41 is composed of a smooth surface portion 52 that is a smooth surface and an uneven surface portion 51 that has a large number of uneven surfaces. The size and arrangement of the smooth surface portion 52 and the uneven surface portion 51 are arbitrary. For example, the entire recess bottom surface portion 50 may be the uneven surface portion 51. It is preferably partitioned into 51. Further, the smooth surface portion 52 is formed around the uneven surface portion 51 , and the smooth surface portion 52 surrounds the uneven surface portion 51 . The shape of the uneven surface portion 51, that is, the shape of the area of the uneven surface portion 51 is also arbitrary.

The uneven surface portion 51 has a large number of convex portions 51a and a large number of concave portions 51b. The concave portion 51b is positioned between the adjacent convex portions 51a. The shape, arrangement, size, etc. of the convex portions 51a of the uneven surface portion 51 are arbitrary, but preferably, the convex portions 51a are ridges extending linearly, and are mesh ridges in which a plurality of ridges intersect in a mesh shape. It is preferable from the viewpoint of preventing the phenomenon that the seal is peeled only in one direction when the seal is peeled, and that the state can be isotropically easily peeled. The mesh ridges may extend along the lid first direction and the lid second direction. is preferably in the range of 40 to 55 degrees, for example. As shown in FIG. 7, the height of the projection 51a, that is, the upward protrusion height T1, is preferably in the range of 0.1 to 0.2 mm, for example. Further, it is preferable that the distance L between adjacent convex portions 51a is, for example, 1 to 2 mm. The uneven surface portion 51 is formed by embossing a synthetic resin sheet forming the lid 3 . Similarly, the area of the convex portion 51a in plan view is preferably smaller than the area of the concave portion 51b. In addition, it is preferable that the total area of the large number of convex portions 51a in the entire uneven surface portion 51 is smaller than the total area of the large number of concave portions 51b.

<Steam release hole 60>
The steam vent holes 60 in the present invention can be of any shape, number, arrangement, etc. For example , they may be curved long holes as shown in FIG. It may be an elongated hole extending in a shape, or may be round as shown in FIG. 10 or 11 . These vapor vent holes 60 are preferably formed by laser processing, because a protective wall can be formed at the opening edges of the holes.

Here, when the steam vent hole 60 is a curved elongated hole, it may be wavy or sinusoidal. Moreover, it is preferable that the steam release hole 60 crosses the protrusions (ridges) of the uneven surface portion 51, and in particular, it is preferable that it crosses many protrusions from the viewpoint of liquid leakage prevention. Among these, from the viewpoint of reducing the sealing area, a curved elongated hole is preferable because a wide opening area can be secured within a certain area. In addition, the width of the curved long hole is preferably in the range of 0.3 to 0.7 mm, particularly 0.4 to 0.6 mm, from the viewpoint of facilitating escape of steam during cooking and ensuring appropriate internal pressure. , the linear length from one end to the other in the longitudinal direction of the slot is preferably in the range of 1.8 mm to 2.5 mm.

Furthermore, it is preferable that a plurality of steam vent holes 60 are provided, and that they are arranged in a predetermined array. An example of the shape of the steam vent hole 60 is shown in FIG. It is preferable that the plurality of steam vent holes 60 have the same shape. It is preferable that the plurality of steam vent holes 60 are arranged in a row in a predetermined direction. For example, in FIG. ing. When a plurality of steam vent holes 60 are provided, it is preferable that the total area of them is in the range of 50 to 90 mm ² from the viewpoint of achieving an appropriate internal pressure and enhancing the steaming effect.

Further, when the steam vent hole 60 is a curved long hole, the distance S (see FIG. 5) between each long hole is preferably in the range of 4 to 7 mm. That is, if the distance S between the long holes becomes too short, the strength of the portion between the curved long holes decreases, causing deformation against the internal pressure during cooking, increasing the amount of steam discharged, and reducing the internal pressure. It becomes difficult to obtain the effect of inviting and steaming. On the other hand, if the distance S between the long holes is too long, it is necessary to increase the area of the uneven surface portion 51 and the sealing area, which impairs the appearance of the product.

In addition, when the projections 51a are formed in a grid pattern on the uneven surface portion 51, the curved steam vent holes 60 are such that the length direction of the elongated holes is at an angle of 40 to 50° with respect to the direction of the projections 51a. It is preferably formed in the range. In FIG. 4 , a steam vent hole 60 for discharging steam is formed in the recess bottom surface portion 50 of the first top surface recess portion 41 . The steam release hole 60 is a through hole vertically penetrating the recessed bottom surface portion 50 of the first top surface recessed portion 41 . The steam release hole 60 is provided in the uneven surface portion 51 . The steam release hole 60 is preferably provided only within the uneven surface portion 51 and does not protrude outside the uneven surface portion 51, but a part of it may protrude.

<Defense wall>
A first protection wall 61 is preferably formed along the entire periphery of the opening edge of the steam vent hole 60 . The first protection wall 61 is preferably annular. The first protection wall 61 protrudes upward from the upper surface of the recess bottom portion 50 of the first top surface recess 41 . As shown in FIG. 7, it is preferable that the projection height T2 of the first protection wall 61 on the upper surface is higher than the projection height T1 of the convex portions 51a of the uneven surface portion 51 .

The first protection wall 61 can be formed, for example, when forming the steam vent hole 60 with a laser. The first protective wall 61 can be formed by adjusting the laser output and the like, and the projection height T2 of the first protective wall 61 can be adjusted.

Incidentally, as shown in FIG. 7, the annular second protection wall 62 may be provided on the bottom surface of the recess bottom surface portion 50 of the first top surface recess portion 41 as well as on the top surface. A first protection wall 61 protrudes upward from the upper surface of the recess bottom surface portion 50 of the first top surface recess portion 41 and a second protection wall 62 is provided downward from the lower surface of the recess bottom surface portion 50 of the first lid top surface portion 30. , the projection height T2 of the first protection wall 61 may be greater than the projection height T3 of the second protection wall 62 . The second protective wall 62 can also be formed by adjusting the laser output in the same manner as the first protective wall 61, and the projection height T3 can also be adjusted.

8 to 11 show other examples of the steam vent hole 60. FIG. The steam vent hole 60 may be, for example, an elongated hole extending linearly rather than corrugated as shown in FIG. 8, or may be an elongated hole elongated in the first direction of the lid. The steam vent holes 60 may be arranged in the lid first direction and the lid second direction. As shown in FIG. 9, the steam release hole 60 may be an elongated hole extending in the second direction of the lid. As shown in FIG. 10, the steam vent holes 60 may be round holes instead of long holes. Also in this case, it is preferable that the round steam vent hole 60 crosses the convex portion 51a of the concave-convex surface portion 51 at least at one point. It should be noted that the steam vent hole 60 does not have to traverse the convex portion 51a of the uneven surface portion 51 as shown in FIG. The protrusions 51a of the concave-convex surface portion 51 may not have a mesh shape. It may be only. Further, the convex portions 51a of the uneven surface portion 51 may be island-shaped such as round or rectangular instead of linearly extending ridges. Also in these shapes, the first protection wall 61 may protrude upward from the opening edge of the steam vent hole 60 .

<Seal 4>
As shown in FIGS. 2 , 4 and 6 , a seal 4 is attached to the recessed bottom surface portion 50 of the first top surface recessed portion 41 to block the steam vent hole 60 . The sticker 4 may be adhered in any manner, but if a plurality of steam vent holes 60 are provided as shown in FIG. affixed. The seal 4 is adhered to the first defense wall 61 and to the convex portion 51a. The seal 4 may be attached to the convex portion 51a and the concave portion 51b. A portion of the seal 4 may be adhered to the smooth surface portion 52 . For example, the peripheral portion of the seal 4 may be adhered to the smooth surface portion 52 . The size of the seal 4 may be larger or smaller than the uneven surface portion 51 , and the seal 4 may be attached only to the uneven surface portion 51 so as not to protrude into the smooth surface portion 52 . In order to further enhance the liquid leakage prevention effect, it is preferable that the adhesive is adhered so as to extend over the smooth surface portion 52 and completely cover the uneven surface portion 51 .

The seal 4 is adhesive, for example, and may be affixed to the lid 3 before the lid closing operation, or may be affixed to the lid 3 after the lid is closed. The seal 4 may be an adhesive label. The seal 4 may have a multilayer structure, for example, a laminated film of two or more types of heat-shrinkable films with different shrinkage rates, or a laminated film of a heat-shrinkable film and a non-shrinkable film. In these cases, it is desirable to use the adhesive surface so that the multilayer film has a lower heat shrinkage.

The body flange portion 12, the middle plate flange portion 22, and the lid flange portion 32 are formed with a large number of extremely thin irregularities to reinforce them and prevent fingers from being cut even if they come into contact with them. may be made The unevenness may be formed only on the outer edge side of the flange portion, or may be formed over the entire width of the flange portion. The unevenness has a wavy shape when viewed enlarged from the front, and the directions of many peaks and valleys are along the inside and outside directions of the container. When the flange portion has a corner portion, it may be formed parallel to the direction connecting the corner portion and the center of the container. Further, the unevenness is formed by, for example, flat knurling or twilled knurling, and is preferably formed by twilled knurling in order to prevent slippage.

For the container body 1, the inner plate 2, and the lid 3, synthetic resin sheets such as polyethylene terephthalate, polystyrene, and polyolefins such as polypropylene and polyethylene, which are heat-resistant and can be used in microwave ovens, can be used. . Moreover, as these sheet materials, a sheet obtained by filling the above-mentioned synthetic resin with an inorganic substance, a foamed sheet obtained by foaming the above-mentioned synthetic resin, or a stretched sheet obtained by stretching the above-mentioned sheet can be used. Among these, heat-resistant foamed styrene resin sheets using heat-resistant styrene resin with excellent heat resistance as polystyrene, sheets made by filling or foaming inorganic substances in polypropylene with excellent heat resistance, polyethylene terephthalate, polystyrene, A heat-resistant sheet obtained by stretching a sheet of polypropylene, polyethylene, or the like to improve heat resistance can be used and thermoformed.

In particular, among these sheets, when a sheet having excellent transparency is used for the lid 3, it is preferable because the stored food can be visually recognized. Among them, a uniaxially or biaxially oriented oriented sheet of transparent polyethylene terephthalate, polystyrene, polypropylene or the like is preferable because it has heat resistance necessary for microwave heating. Moreover, the polystyrene sheet (OPS) is preferable to the polyethylene terephthalate sheet because it has a larger contact angle and the liquid is less likely to leak outside from the vapor release holes 60 . A container using a heat-resistant foam material for the container main body 1 is suitable because it does not get hot even when held with a bare hand when heated in a microwave oven, and is excellent in heat retention.

As described above, the uneven surface portion 51 is provided with the steam vent holes 60, and the seal 4 is adhered to the uneven surface portion 51, thereby preventing liquid leakage from the steam vent holes 60 during transportation, store display work, and the like. definitely prevented. Since the steam vent hole 60 is closed by the seal 4, foreign matter such as insects are prevented from entering the container through the steam vent hole 60.例文帳に追加

In addition, since the seal 4 is attached to the recess bottom portion 50 of the first top surface recess 41, other objects are less likely to come into contact with the seal 4 during transportation or display at the store. When the containers are stacked vertically, the upper container is less likely to come into contact with the seal 4 of the lower container. Therefore, the seal 4 is not easily peeled off during transportation or display, and it is possible to reliably prevent contamination by foreign matter such as insects, and to reliably prevent liquid leakage.

When the food, which is the content, is heated by a microwave oven, if the internal pressure of the container rises above a certain level, the internal pressure acting on the seal 4 through the steam vent hole 60 causes the seal 4 to peel off and the steam vent hole 60 to heat the food. Steam is discharged outside the container. Therefore, it is possible to prevent the cover from flying due to an increase in internal pressure. Since the seal 4 is affixed to the convex portion 51a of the uneven surface portion 51, the seal 4 is reliably peeled off due to the increase in internal pressure, and the steam is discharged. In addition, due to the size effect of the steam release hole 60, it is possible to maintain an appropriate internal pressure, obtain a steaming effect, and quickly heat and cook.

If the convex portion 51a of the uneven surface portion 51 is a linearly extending ridge and the steam vent hole 60 crosses the ridge, the convex portion 51a is reliably positioned adjacent to the steam vent hole 60. . Therefore, the seal 4 attached to the convex portion 51a can reliably prevent liquid leakage from the steam vent hole 60, and can reliably discharge steam during heating in the microwave oven.

Furthermore, if the first protection wall 61 is provided at the opening edge of the steam vent hole 60, the seal 4 is adhered to the first protection wall 61, so that the liquid leakage prevention effect of the seal 4 is enhanced. Further, the seal 4 is peeled off from the first protection wall 61 during heating in the microwave oven so that the steam can be discharged smoothly. In particular, when the protrusion height of the first protection wall 61 is higher than the protrusion height of the convex portion 51a of the uneven surface portion 51, the seal 4 is reliably adhered to the first protection wall 61, and the liquid Leakage can be effectively prevented. Moreover, the first protection wall 61 itself increases the surface tension in the steam vent hole 60, thereby enhancing the liquid leakage prevention effect. If the second protection wall 62 is provided on the lower surface, the surface tension is further increased, and the liquid leakage prevention effect is enhanced.

1 container body 2 middle plate 3 lid 4 seal 5 band label 10 body bottom portion 11 body side surface portion 12 body flange portion 13 first body fitting portion 14 second body fitting portion 15 stepped portion 20 middle plate bottom portion 21 middle plate Side portion 22 Middle plate flange portion 23 Middle plate fitting portion 24 Swelling portion 25 Steam discharge valve 26 Middle plate knob portion 27 Anti-blocking convex portion 30 Lid top surface portion 31 Lid side portion 32 Lid flange portion 33 Lid fitting portion 34 Lid horizontal portion 35 Lid knob portion 36 Anti-blocking convex portion 37 Stacking convex portion 38 Inclined surface 41 First top surface concave portion 42 Second top surface concave portion 50 Bottom surface portion 51 Concave and convex surface portion 51a Convex portion 51b Concave portion 52 Smooth surface portion 60 steam vent hole 61 first protection wall 62 second protection wall

Claims (4)

A lid fitted to a container body of a microwave oven container, which is a thermoformed product of a synthetic resin sheet,
a top surface, a side surface extending downward from the outer edge of the top surface, and a flange provided outside the side surface;
A stacking projection is provided on the peripheral edge of the top surface to project upward to prevent misalignment of containers when the containers with lids are stacked one on top of the other.
At a position spaced from the stacking protrusion toward the center of the lid on the top surface, there is a top surface recess that is recessed downward so that the bottom surface of the recess is located below the base end of the stacking protrusion. provided,
An uneven surface portion having a large number of unevenness is provided on the bottom surface of the recessed portion of the top surface recessed portion, and a steam vent hole is provided in at least the recessed portion of the uneven surface portion, and
An annular protective wall is provided at the opening edge of the steam vent hole, protruding higher than the convex portion of the uneven surface portion and having a height lower than the depth of the concave portion of the top surface,
A lid for a container for a microwave oven, wherein a seal for closing a steam vent hole is attached to the bottom surface of a concave portion of a concave portion on the top surface. 2. The lid of the microwave oven container according to claim 1, wherein the projections of the uneven surface portion are ridges extending linearly, and the vapor vent hole continuously crosses the plurality of projections and recesses . 3. The microwave container lid according to claim 2 , wherein the steam vent hole is a curved elongated hole. A microwave oven container comprising a container body and a lid made of a thermoformed synthetic resin sheet fitted to the container body,
The lid includes a top surface, a side surface extending downward from the outer edge of the top surface, and a flange provided outside the side surface,
A stacking projection is provided on the peripheral edge of the top surface of the lid to protrude upward to prevent misalignment of the containers when the containers with the lids closed are stacked one on top of the other.
At a position spaced from the stacking protrusion toward the center of the lid on the top surface of the lid, the top surface is recessed downward so that the bottom surface of the recess is positioned below the base end of the stacking protrusion. A recess is provided,
An uneven surface portion having a large number of unevenness is provided on the bottom surface of the recessed portion of the top surface recessed portion, and a steam vent hole is provided in at least the recessed portion of the uneven surface portion, and
An annular protective wall is provided at the opening edge of the steam vent hole, protruding higher than the convex portion of the uneven surface portion and having a height lower than the depth of the concave portion of the top surface,
A container for a microwave oven, wherein a seal for closing a steam vent hole is adhered to the bottom surface of the concave portion of the top surface concave portion.

Images