JP2002173127A - Rice container such as lunchbox - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rice container such as a lunchbox wherein rice is difficult to attach to an internal surface of the container so that the rice can be easily separated. SOLUTION: Numerous linear narrow grooves extending approximately in parallel and narrow ribs located between the grooves are formed approximately on an entire internal surface of the container for receiving rice. At least a surface of each rib is dotted with vermicular dents different in size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for cooked rice, such as a lunch box, and more particularly to a container in which cooked rice is difficult to adhere to the inner surface of the container and the rice can be easily removed.

[0002]

2. Description of the Related Art Conventionally, there has been provided a lunch box provided with a container for accommodating cooked rice, and a container for cooked rice capable of accommodating cooked rice as a food lid. Such a container is usually formed by injection molding of a resin such as polypropylene.
It is formed as an upper opening-shaped container integrally having a bottom wall and a side wall.

[0003]

In the conventional container, the entire inner surface of the bottom wall and the side wall is formed as a smooth surface, so that the stored cooked rice is easily attached thereto. That is, when the cooked hot rice is stored in the container, the rice grains are pressed against the inner surface of the container and adhere.
While the cooked rice is warm, the sticky rice grains can be relatively easily peeled off from the inner surface of the container, but as the cooked rice cools, the adhesive portion solidifies and adheres to the inner surface of the container.

Therefore, when rice cooked in a container, such as a lunch box, is eaten after being cooled for a predetermined time, the rice particles adhered to the inner surface of the container are difficult to peel off. It is common to be left behind,
Waste food resources. Then, when cleaning the container, the remaining rice grains are dried and solidified and adhere more strongly to the inner surface of the container, so that it is not easy to wash off the rice grains, and the cleaning operation becomes difficult.

[0005] In this regard, the present inventor has found that if the inner surface of the container is formed with a rough surface, the adhesion of rice grains is reduced, and the above-mentioned problem can be solved. However, for example, even if the rough surface is simply formed by Rinchi ground, the warm rice cooked immediately after cooking is soft, so that it easily adjusts to and adheres to Rinchi ground, and because it contains abundant moisture, the aqueous starch solution is It is easy to form a glue film between Riko ground and rice grain,
Eventually, as the cooked rice cools, the rice grains adhere to the inner surface of the container with difficulty in peeling, and the above problem cannot be solved.

[0006]

Means for Solving the Problems For this reason, the present inventor has proposed:
As a result of intensive studies on the shape and other properties of cooked rice, it is necessary to always make the adhesion area between the inside surface of the container and the rice grain as small as possible, even when the rice grain comes into contact with the inside surface of the container from any direction and in any direction. This reduces the adhesion of the rice grains, thereby facilitating the peeling of the rice grains.Even if the rice grains adhere and remain and solidify, the dried and adhered rice grains can be easily washed off when washing the container later. We have realized a cooked rice container such as a lunch box.

Therefore, the present invention is configured as a first means in that a large number of linear narrow grooves extending substantially in parallel and located between the narrow grooves are provided on substantially the entire inner surface of the container for storing cooked rice. It is characterized in that a strip-shaped ridge is formed, and at least the surface of each ridge is dotted with worm-like recesses of different sizes.

Further, the present invention is configured as a second means, in a container for storing cooked rice having a side wall rising from each side of a bottom wall having a long side and a short side, wherein an inner surface of the bottom wall is provided. A large number of linear narrow grooves extending substantially parallel to the long side of the bottom wall and a narrow band-like ridge located between the narrow grooves are formed on almost the entire surface of the ridge, and at least the surface of the ridge has a small and large insect-eating shape. Are formed by scattered concave portions, and substantially all over the inner surface of the side wall,
A large number of linear narrow grooves extending almost parallel to the bottom wall in a substantially vertical direction, and forming a narrow band-shaped ridge located between the narrow grooves,
In other words, at least the worm-like concave portions are scattered on the surface of the ridge portion.

In the embodiment of the present invention, it is preferable to injection mold a rice cooker with a resin obtained by adding and mixing silicon to polypropylene. According to the findings of the present inventor, when silicone is mixed with polypropylene, the adhesion of rice grains to the surface of a molded container is greatly reduced, and the surprising result that the peelability of rice grains is extremely good is obtained. found.

For the purpose of the present invention, the shape of the grooves and ridges alternately arranged on the inner surface of the container is such that the depth of the grooves is 0.2-0.4 mm, preferably 0.1 mm. The width of the narrow groove is preferably 0.4 to 0.6 mm, more preferably 0.3 mm.
It is good to be 5mm. The width of the ridge is 1.0 to
It is good to be 1.4 mm, preferably 1.25 mm, and furthermore, it is good to form a round surface on both shoulders of the ridge.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a lunch box as an example of an embodiment of the present invention. However, the present invention is not limited to the lunch box as shown in FIG. It is to be understood that a rice container for accommodating the rice is included.

In the illustrated embodiment, a lunch box comprises a rice-cooked rice container 1 (hereinafter referred to as a main container 1) having an upper opening, an inner lid 2 for opening and closing the upper opening of the container 1, and an inner lid 2 And a side container 3 (hereinafter referred to as an auxiliary container 3) having an upper opening shape and an upper lid 4 for opening and closing the upper opening of the auxiliary container 3 so as to be openable and closable.

The main container 1 comprises a box-shaped container having a side wall 6 rising from each side of a substantially rectangular bottom wall 5 having a long side and a short side, and a pair of side walls 6 extending along the long side. A locking edge 7 is provided at the opening edge and protrudes outward.

The inner lid 2 constitutes a dish-shaped body 8 which is recessed downward from the top so as to be removably fitted into the upper opening of the main body container 1, and is formed on the top of the side wall 6 of the main body container 1. And a knob 10 to be mounted on the locking rim 7 so as to protrude from the flange 9.

The auxiliary container 3 constitutes a box-shaped container having a side wall 12 rising from each side of a substantially rectangular bottom wall 11 having a long side and a short side, and a portion extending from the side wall 12 to the bottom wall 11. In addition, a step wall 13 is formed so as to be removably fitted into the upper opening of the dish-shaped body 8 constituting the inner lid 2. A removable partition plate 14 is provided inside the auxiliary container 3, and the partition plate 14 is slidable along the inner surface of the bottom wall 11.

The upper lid 4 constitutes a downwardly facing dish-like body which covers the upper opening of the auxiliary container 3 so as to be openable and closable. The upper lid 4 is opened by an elastic packing (not shown) provided on the lower peripheral portion. Seal the edges. In the case of the example shown in the figure, the upper lid 4 has a chopstick case storage room 15 recessed in the upper surface thereof.
5 is provided with an opening / closing lid 16 for opening and closing the opening 5 freely. Note that locking ear pieces 17 are rotatably connected to both side edges of the upper lid 4.

In the lunch box having such a structure, after the cooked rice is stored in the main container 1 and the side dishes and / or the cooked rice are stored in the auxiliary container 3, the upper opening of the main container 1 is covered with the inner lid 2. The stepped wall 13 of the auxiliary container 3 is provided in the upper opening of the inner lid 2.
After that, the upper opening of the auxiliary container 3 is covered with the upper lid 4, and in such a laminated state, the locking ear piece 17 of the upper lid 4 is rotated, and the locking rib of the locking ear piece 17 is rotated. 17a is fixed by locking to the locking edge 7 of the main body container 1.

Therefore, the inner surface structure of the container intended by the present invention is provided in the main container 1 and / or the auxiliary container 3. That is, it may be provided in one of the main container 1 and the auxiliary container 3, or may be provided in both the main container 1 and the auxiliary container 3. Alternatively, in addition to a lunch box having a laminated structure as shown in the figure, a lunch box of a type in which the main body container 1 is directly covered with the upper lid 4 may be used. In this case, the inner surface structure of the present invention is a matter of course. It is provided in the main body container 1.

In the illustrated embodiment described here, the inner surface structure provided in the main body container 1 will be described in detail for convenience of explanation.

As described above, the main body container 1 constitutes a box-shaped container having side walls 6 rising from each side of a substantially rectangular bottom wall 5 having a long side and a short side. Silicon is added to polypropylene. It is injection molded with the mixed resin. In addition, the bottom wall 5 of the main container 1 may be an elliptical shape or an elliptical shape other than a substantially rectangular shape as shown in the figure, that is, a horizontally long shape having a long side (long axis) and a short side (short axis) A shape (or a vertically long shape) is employed.

Therefore, as shown in FIGS. 1 and 2, a large number of linear narrow grooves 18a extending substantially parallel to the long side of the bottom wall 5 are formed on almost the entire inner surface of the bottom wall 5. Grooves 18a, 18
A narrow band-shaped ridge 19a located between the ridges 19a is formed, and at least the surface of the ridge 19a is dotted with worm-like concave portions 20a of different sizes. In the case of the example shown in FIG.
The recesses 20a are scattered only in the thin grooves 9a.
It is preferable that the recesses 20a are also dotted at the bottom of the groove a.

Similarly, on almost the entire inner surface of the side wall, a large number of linear narrow grooves 18b extending substantially parallel to the bottom wall 5 in a substantially vertical direction, and narrow lines located between the narrow grooves 18b, 18b. A band-shaped ridge 19b is formed, and at least the surface of the ridge 19b is dotted with worm-like recesses 20b of different sizes. Also in this case, it is preferable that the concave portions 20b be dotted not only at the ridge portions 19b but also at the groove bottoms of the narrow grooves 18b.

By the way, as shown in FIG.
And 18b have a depth h of 0.2 to 0.4 mm, preferably 0.3 mm. This depth dimension h is
The groove bottoms of the narrow grooves 18a and 18b and the ridges 19a and 19b
Appears as a height difference between the top and the top.

The width w1 of the narrow grooves 18a and 18b
And the width dimension w2 of the ridges 19a and 19b is w1 <w2
Is formed. At this time, the width dimension w1 of the narrow grooves 18a and 18b is 0.4 to 0.6 mm, preferably 0.5 mm
And the width dimension w2 of the ridge portions 19a and 19b is
It is formed to have a thickness of 1.0 to 1.4 mm, preferably 1.25 mm.

In the illustrated example, the surfaces of the ridges 19a and 19b are formed in an arc shape in cross section, and the arc radius R is set to 0.7 to 0.
9 mm, preferably 0.8 mm, but the ridges 19a
And 19b may be formed so that the top surface is substantially horizontal. In any case, it is preferable to form the round surface 21 on both shoulders of the ridges 19a and 19b.

When rice cooked immediately after cooking is put into the main body container 1 and observed for an experiment based on such a configuration, as shown in FIG. 2, the rice grains 22 are in any posture with respect to the inner surface of the main body container 1. Even when touching from the direction, rice grains 22
Is always over a plurality of ridges 19a straddling the narrow grooves 18a and 18b.
And 19b. That is, the rice grains 22 are ridged portions 19a.
Or, when facing in a direction orthogonal to 19b, it always straddles three or more ridges 19a or 19b, and ridges 19a or 19b.
b, even when facing in a direction parallel to b.
It straddles 9a or 19b. And the rice grains 22 and the ridges 19
a and 19b are provided with a large number of worm-like recesses 20 in the contact surface.
It was confirmed that the adhesion of the rice grains 22 to the inner surface of the container 1 was extremely reduced due to the presence of a and 20b. Further, the both sides of the ridges 19a and 19b have a round surface 2
Since 1 is formed, both shoulders of the ridge do not bite into pressed rice grains 22. In particular, when the cooked rice was eaten with chopsticks after cooling, the rice grains 22 attached to the inner surface of the main body container 1 (the inner surface of the bottom wall 5 and the inner surface of the side wall 6) could be peeled off very easily.

In addition, under the same structure using the same mold, a main body container injection-molded only with polypropylene (comparative product) and a main body container injection-molded with a resin obtained by adding silicone to polypropylene and mixing the same (the present invention) In comparison with the comparative example, it was confirmed that the adhesion of the rice grain to the inner surface of the container was surprisingly significantly reduced and the peeling was extremely easy according to the comparative example. .

Then, after a large number of rice grains are dried and solidified on the inner surface of the main body container 1 (the inner surface of the bottom wall 5 and the inner surface of the side wall 6), the main body container 1 is washed with water. 22 could be washed off very easily. The water poured into the main body container 1 has the narrow grooves 18a and 18b.
And penetrates almost all over the bottom wall 5 and the side wall 6 and penetrates between the rice grain 22 and the wall face through the narrow grooves 18a and 18b, thereby causing the rice grain 22 to float. Further, the water flows from the narrow grooves 18a and 18b to the worm-like concave portions 2 of the ridge portions 19a and 19b.
It is considered that this is because they penetrate into Oa and 20b and soften the glue film of the rice grains 22.

Further, when the inner surface of the main body 1 is brushed with a cleaning brush, the brush bristles move along the narrow grooves 18a or 18b and the ridges 19a or 19b which are arranged substantially in parallel. And the starch paste film could be washed off very suitably. In particular,
In the bottom wall 5, the narrow groove 18a and the ridge 19a extend in the longitudinal direction, and in the side wall 6, the narrow groove 18b and the ridge 1
Brushing is easy because 9b is arranged in the vertical direction.

By the way, the main body container 1 injection-molded with a resin obtained by adding and mixing silicone to polypropylene.
Is higher in flexibility and inferior in shape retention as compared to a container formed only from polypropylene. In this regard, when the narrow grooves 18a and the ridges 19a are arranged in the short side direction of the bottom wall 5, the shape retention of the bottom wall 5 is further reduced.
As described above, in the present invention, the narrow groove 18a and the ridge 1
9a is arranged substantially in parallel along the long side of the bottom wall 5, whereby the horizontally long bottom wall 5 is reinforced in the longitudinal direction and the shape retention is improved.

[0032]

According to the present invention, even when the rice grains 22 come into contact with the inner surface of the container 1 from any direction and in any direction, the rice grains 22 are always in a plurality of ridges 19a and 19b.
, And is always located on the narrow groove 18a or 18b. And since many worm-like concave parts 20a and 20b are formed in the ridge parts 19a and 19b,
The adhesion area of the rice grains 22 is made as small as possible, and as a result,
There is an effect that the adhesive force of the rice grains 22 is reduced and the peeling of the rice grains 22 is facilitated.

Then, when the container 1 is molded from a resin obtained by adding silicone to polypropylene and mixing, the container 1
The adhesion of the rice grains 22 to the inner surface of the flakes is extremely reduced, and it is extremely easy to peel off.

Further, even when the rice grains 22 are adhered and remain and are solidified, when the container 1 is washed, the dried and fixed rice grains 2
2 has an effect that it can be easily washed off.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a lunch box according to one embodiment of the present invention.

FIG. 2 is a perspective view showing an example of the structure of the present invention formed on the inner surface of the container.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body container (rice rice container) 5 Bottom wall 6 Side wall 18a, 18b Narrow groove 19a, 19b Ridge part 20a, 20b Insect-like concave part 21 Earl surface 22 Rice grain

Claims (4)

[Claims] 1. A large number of linear narrow grooves extending substantially in parallel and narrow band-shaped ridges located between the narrow grooves are formed on substantially the entire inner surface of a container for storing cooked rice, and at least each ridge is provided. A container for cooked rice, such as a lunch box, which is formed by scattering worm-like recesses of different sizes on the surface of the rice. 2. A container for storing cooked rice having a side wall rising from each side of a bottom wall having a long side and a short side, wherein substantially the entire inner surface of the bottom wall is substantially flush with the long side of the bottom wall. A large number of linear narrow grooves extending in parallel, and a narrow band-shaped ridge located between the narrow grooves, wherein at least the surface of the ridge is dotted with worm-like concave portions having different sizes, and the inner surface of the side wall A large number of linear narrow grooves extending substantially parallel to the bottom wall in a substantially vertical direction toward the bottom wall, and a narrow band-like ridge located between the narrow grooves are formed on almost the entire surface of the ridge. A container for cooked rice, such as a lunch box, comprising worm-like recesses interspersed. 3. A container for cooked rice such as a lunch box according to claim 1, wherein the container is formed of a resin obtained by adding silicone to polypropylene and mixing the polypropylene. 4. The narrow groove has a depth of 0.2 to 0.4 mm, the narrow groove has a width of 0.4 to 0.6 mm, and the ridge has a width of 1.0.
The container for cooked rice such as a lunch box according to claim 1, 2 or 3, wherein a round surface is formed on both shoulders of the ridge portion.