Disposable food container consisting of a polypropylene inner shell and a paper outer shell.

Abstract

This invention provides a disposable food container that can be safely used in a microwave oven. [Solution] The present invention discloses a disposable microwaveable food container (10) comprising a polypropylene inner shell container body (11) and a paper outer shell (paper cover) (12), wherein a plurality of outwardly protruding hanging protrusions (111) are formed on the outer circumference of the lower part of the container body, and the outer shell (12) is assembled on the outside of the container body (11) and fixed by the plurality of hanging protrusions (111). The paper outer shell (12) is assembled on the outside of the container body (11) and fixed by the plurality of hanging protrusions (111). Therefore, the paper outer shell (12) can be assembled and fixed on the outside of the container body (11) without using adhesive. Preferably, there are 2 to 4 outwardly protruding hanging protrusions (111) formed on the outer circumference of the lower part of the container body (11).

Description

Technical Field

[0001] The present invention relates to a disposable food container for packaging various instant foods such as various noodles like ramen and udon, various soups like miso soup and hot pot, and various beverages such as coffee and tea. More specifically, the present invention relates to a disposable food container for heating and cooking instant foods and beverages such as coffee and tea that need to be heated, which are packaged in a semi-cooked state, in a microwave oven.

Background Art

[0002] Instant foods such as various noodles like cup noodles and cup udon, and various soups like miso soup and hot pot are now very popular foods. Also, beverages such as coffee and tea are very popular consumer goods. These instant foods and beverages are mostly eaten or drunk after pouring boiling water heated to about 100°C and waiting for about 3 to 5 minutes. Until now, containers that can be safely heated have not been developed, which has restricted the development of more diverse and delicious instant foods. Although some instant foods have been developed to be eaten after heating for a certain period of time using a microwave oven, it is difficult to develop containers that meet the heating conditions, and they have not yet been widely used.

[0003] There is a significant difference in taste between instant foods and beverages such as coffee and tea packaged in disposable food containers when cooked by pouring boiling water and when cooked using a microwave oven. Cooking by pouring boiling water has the effect of softening the contents with boiling water, but cooking using a microwave oven has the effect of directly applying heat to boil, so the recipe of the dish changes and the taste changes compared to cooking by pouring boiling water. If instant foods can be cooked in a microwave oven, it is possible to enjoy instant foods that can produce the same taste as boiling directly using gas or electricity.

[0004] Most instant food containers currently on the market are made from thick paper coated with polyethylene (PE) film. Other types of containers have an inner shell made of PE-coated paper, to which an outer shell made of paper is attached. Containers made in this way do not leak water even when boiling water is poured in, so they can be used for cooking with boiling water. However, these containers cannot be used in a microwave oven. The body of a container made of PE-coated paper has a single joint formed vertically, where the body of the container meets the bottom. When these containers are heated in a microwave oven, the contents shake violently as the water boils, causing the PE film to rupture at the joint and leak water.

[0005] Some instant food containers for microwave use are manufactured using heat-resistant polystyrene foam sheets. While polystyrene (PS) foam sheets have excellent heat insulation properties, they have poor heat resistance, making them unsuitable for microwave use. Furthermore, they can release harmful substances when used with boiling water or microwaves.

[0006] Containers using polypropylene instead of polystyrene, which is harmful to the human body, have been developed. Korean Utility Model Publication No. 2000-0007691 and Korean Utility Model Publication No. 2000-0010571 disclose instant containers in which the body of the container, formed by injection molding of polypropylene, has numerous ribs protruding from the surface of the container body to prevent direct contact with the human body. However, because these containers are manufactured by injection molding, they are manufactured to be thick, with a minimum thickness of 0.8 mm or more. Therefore, these containers have high manufacturing costs and have not been commercialized as disposable containers.

[0007] Korean Patent Publication No. 2002-0042464 discloses a polypropylene resin foam container for microwave cooking that does not deform when used in a microwave oven and has excellent heat resistance. This container has a non-foamed layer containing polypropylene resin and talc on at least one surface of the polypropylene resin foam layer. However, this container was not commercialized due to manufacturing difficulties.

[0008] The inventors have developed a disposable food container for use in microwave ovens, manufactured from a sheet made by laminating a polypropylene foam sheet with paper-based printing paper, and have filed a patent application in Korea (Korean Patent Application No. 2020-0043117, published in Korea). However, this container has manufacturing difficulties, specifically in the process of foaming the polypropylene and laminating the foamed sheet with the printing paper. The sides and bottom of the container are separated and then joined together, making the joint fragile. That is, when this container is heated in a microwave oven, there is a very high possibility that the fragile joint will rupture and water will leak out. Furthermore, because the polypropylene sheet and paper are bonded together, separating them is extremely difficult. Therefore, there are serious problems with reuse.

[0009] To solve the aforementioned problems, the inventors developed a disposable food container that can be used in a microwave oven, is easy to manufacture and handle, is easy to separate for recycling, and allows for resource reuse. This container consists of a polypropylene inner shell and a paper outer shell, which are bonded together with an adhesive. The inventors filed a Korean patent application, No. 2024-0006575, for this container. However, it has become clear that this patent application also presents serious problems regarding the reuse of the container due to the adhesive used.

[0010] In the aforementioned patent application, the polypropylene inner casing and the paper outer casing can be easily separated, but adhesive residue remains in the polypropylene inner casing, making it impossible to obtain high-quality recycled plastic raw material. The adhesive residue in the recycled container significantly degrades the quality of the recycled plastic.

[0011] Therefore, the inventors have developed the present invention, a disposable container consisting of a polypropylene inner shell and a paper outer shell, which does not use adhesives. [Prior art documents] [Patent Documents]

[0012] [Patent Document 1] Korean Public Utility Model Publication No. 2000-0007691 [Patent Document 2] Korean Public Utility Model Publication No. 2000-0010571 [Patent Document 3] Korean Published Patent No. 2002-0042464 [Patent Document 4] Korean Published Patent Publication No. 2021-0125681 [Overview of the Initiative] [Problems that the invention aims to solve]

[0013] The object of the present invention is to provide a disposable food container that can be safely used in a microwave oven.

[0014] Another object of the present invention is to provide a disposable container that can be used to eat instant food that can be cooked in a microwave oven to produce a taste similar to that produced by boiling over an open flame, or to drink coffee, tea, etc.

[0015] Another object of the present invention is to provide an environmentally friendly disposable container that consists of a paper outer shell and a polypropylene inner shell, is easy to separate and collect, and can produce high-quality recycled resin without the use of adhesives.

[0016] Another object of the present invention is to provide a disposable food container that is easy to manufacture and has a low manufacturing cost, comprising a paper outer shell and a polypropylene inner shell.

[0017] All of the aforementioned and other objectives of the present invention can be achieved by the present invention, which is described in detail below. [Means for solving the problem]

[0018] The disposable food container (10) for microwave ovens according to the present invention comprises a container body (11) with a polypropylene inner skin and a paper outer skin (paper cover) (12), wherein a plurality of outwardly protruding hanging protrusions (111) are formed on the outer circumference of the lower part of the container body, and the outer skin (12) is assembled on the outside of the container body (11) and fixed by the plurality of hanging protrusions (111).

[0019] The polypropylene inner lining container body (11) is molded to a minimum thickness of approximately 0.3 to 1.0 mm, which is sufficient to maintain heat resistance and shape. Relatively thin containers are manufactured from polypropylene resin by vacuum molding or air press molding, while relatively thick containers are manufactured by injection molding. Since the inner lining container is molded as a single unit without any joints, there is no risk of it bursting in any part when used in a microwave oven.

[0020] The paper outer shell (12) is assembled on the outside of the container body (11) and secured by the plurality of hanging protrusions (111). Therefore, the paper outer shell (12) can be assembled and secured on the outside of the container body (11) without using adhesive. The paper outer shell (12) can also be manufactured in a cylindrical shape and physically assembled on the outside of the container body (11), or a flat, cut outer shell paper can be wrapped around the container body (11) and its ends can be glued together. In this case, the adhesive used is applied only to the outer shell paper and not to the container body (11).

[0021] The number of hanging protrusions (111) formed on the outer circumference of the lower part of the container body (11) is preferably 2 to 4.

[0022] The paper outer skin (12) is printed with the necessary content for product description, provides heat insulation, and serves as a label while maintaining the formability of the container.

[0023] The container body (11) with an inner skin made of polypropylene has unevenness (wave-like) formed in the vertical direction, which can improve the strength and heat insulation effect of the container.

[0024] The food container (10) of the present invention can easily separate the paper outer skin (12) fixed by the hanging protrusions (111) from the container body (11). Therefore, the paper outer skin (12) and the plastic container body (11) can be separated and reused respectively. Since there is no residue of adhesive on the container body (11), high-quality recycled resin can be produced.

[0025] Instant foods, coffee, or tea packaged in the food container (10) according to the present invention can be eaten or drunk after being heated in a microwave oven for 3 to 5 minutes depending on the contents. The container (10) of the present invention has no problem even when heated at 100°C for 10 minutes or more. Since the instant foods heated in this way in a microwave oven bring the effect of directly boiling, they can produce a better taste compared to instant foods and beverages prepared by pouring hot water to expand the contents.

[0026] Hereinafter, the specific content of the present invention will be described in detail with reference to the attached drawings.

Effect of the Invention

[0027] The present invention has the effect of an invention that can be safely used in a microwave oven, and by cooking or heating in a microwave oven, one can eat instant foods that can produce the same taste as directly boiling, drink coffee, tea, etc., and is composed of a paper outer skin and a container with an inner skin made of polypropylene, which is easy to separately collect, and without using an adhesive, high-quality recycled resin can be produced, providing an environmentally friendly disposable container.

Brief Description of the Drawings

[0028] [Figure 1] This is a schematic perspective view of a food container (10) according to one specific example of the present invention, in which a paper outer shell (paper cover) (12) is assembled to the outside of a molded plastic container body (11), and the outer shell (12) is fixed by a plurality of hanging protrusions (111) integrally formed on the lower outer circumference of the container body (11). [Figure 2] Figure 1 is a schematic exploded perspective view of the food container (10). [Figure 3] This is a schematic perspective view illustrating the state in which the ends of a flat, cut outer layer of paper are glued together to wrap around the container body (11). [Modes for carrying out the invention]

[0029] The present invention relates to a disposable food container for packaging various types of noodles such as ramen and udon, various types of soups such as miso soup and hot pot, and various beverages such as coffee and tea. More specifically, it relates to a disposable food container for heating and cooking instant foods that are packaged in a semi-cooked state, or beverages such as coffee and tea that require heating, in a microwave oven.

[0030] Figure 1 is a schematic perspective view of a food container (10) according to a specific example of the present invention, in which a paper outer shell (paper cover) (12) is assembled to the outside of a molded plastic container body (11), and the outer shell (12) is fixed by a plurality of hanging protrusions (111) integrally formed on the outer circumference of the lower part of the container body (11). Figure 2 is a schematic exploded perspective view of the food container (10) of Figure 1.

[0031] The disposable food container (10) for microwave ovens according to the present invention consists of a container body (11) made of polypropylene and a paper outer shell (paper cover) (12), wherein a plurality of outwardly protruding hanging protrusions (111) are formed on the outer circumference of the lower part of the container body, and the outer shell (12) is assembled on the outside of the container body (11) and fixed by the plurality of hanging protrusions (111).

[0032] The polypropylene inner lining container body (11) is molded to a minimum thickness of approximately 0.3 to 1.0 mm, which is sufficient to maintain heat resistance and shape. Relatively thin containers are manufactured from polypropylene resin by vacuum forming or pressure forming, while relatively thick containers are manufactured by injection molding. Since the inner lining container body is molded as a single unit without any joints, there is no risk of it bursting in any part when used in a microwave oven.

[0033] The paper outer shell (12) is assembled on the outside of the container body (11), and its lower outer circumference is secured by the plurality of hanging protrusions (111). The upper outer circumference of the outer shell (12) is inserted into and secured in the groove on the lower side of the upper outer circumference of the container body (11). The paper outer shell (12) can be assembled and secured on the outside of the container body (11) without using adhesive.

[0034] The paper outer shell (12) can be pre-fabricated in a cylindrical shape and physically assembled to the outside of the container body (11), or a flat, cut outer shell can be wrapped around the container body (11) and its ends can be glued together. Figure 3 is a schematic perspective view showing the state in which the ends of a flat, cut outer shell are glued together to wrap around the container body (11). The adhesive used in this case is applied only to the outer shell and not to the container body (11).

[0035] The outer hanging protrusions (111) formed on the lower outer circumference of the container body (11) are preferably 2 to 4 in number. Three or four hanging protrusions are more preferable.

[0036] The paper outer layer (12) is printed with the necessary information to describe the product, and serves as a label while providing heat insulation and maintaining the shape of the container. The process of manufacturing and printing the paper outer layer (12) can be easily carried out by those skilled in the art to which the present invention belongs.

[0037] The polypropylene inner lining of the container body (11) has a wavy (corrugated) surface formed in the vertical direction, which can improve the strength and heat insulation effect of the container. The shape of the wavy surface and the shape of the container body can be varied depending on the contents of the product.

[0038] The food container (10) of the present invention allows the paper outer shell (12), which is fixed by a hooking projection (111), to be easily torn by hand along the perforations and separated from the container body (11). Separation can be achieved by applying physical force by hand or by tearing the paper outer shell. The separated paper outer shell (12) and the plastic container body (11) can be reused. Since there is no adhesive residue in the container body (11), high-quality recycled resin can be produced.

[0039] Instant foods, coffee, or tea packaged in the food container (10) according to the present invention can be eaten or drunk after being heated in a microwave oven for 3 to 5 minutes, depending on the contents. The container (10) of the present invention can withstand heating at 100°C for 10 minutes or more without any problems. Because instant foods heated in a microwave oven in this way have the effect of being directly boiled, they can produce a better taste compared to instant foods or beverages that are cooked by pouring hot water over the contents and letting them soften.

[0040] Simple modifications or alterations of the present invention can be readily carried out by a person with ordinary skill in the art, and all such modifications or alterations fall within the scope of the present invention. [Explanation of symbols]

[0041] 10 containers 11 Container body 12. Outer covering (paper cover) 111 Hanging protrusion

Claims

1. A disposable microwaveable food container (10) is characterized by comprising a polypropylene inner shell container body (11) and a paper outer shell (paper cover) (12), wherein a plurality of outwardly protruding hanging protrusions (111) are formed on the outer circumference of the lower part of the container body, and the outer shell (12) is assembled on the outside of the container body (11) and fixed by the plurality of hanging protrusions (111).

2. The container body (11) of the polypropylene inner skin is manufactured by vacuum molding, air press molding, or injection molding to a minimum thickness of approximately 0.3 to 1.0 mm that can maintain heat resistance and shape retention, making it a disposable microwave food container (10) according to claim 1.

3. The microwaveable disposable food container (10) according to claim 1 or 2, characterized in that two to four of the aforementioned hanging protrusions (111) are formed therein.

4. The disposable microwaveable food container (10) according to claim 3, characterized in that the paper outer shell (12) is fixed to the outside of the container body (11) by the hanging protrusions (111) without the use of adhesive.

5. The aforementioned paper outer shell (12) provides heat insulation and maintains the container's shape while serving as a label on which the necessary information for describing the product is printed, as described in claim 4 for the microwave-safe disposable food container (10).

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