High-airtightness food container

Abstract

The invention provides a high-airtightness food container which comprises a container body, the container body is formed by folding sheet-shaped paper, the upper end of the container body is open, the container body is provided with a bottom wall and a peripheral wall adjacent to the bottom wall, and at least one seam line is formed on the bottom wall or the peripheral wall. The seam line is located at a seam formed by overlapping at least two layers of sheet-shaped paper materials, and an edge seam position is formed at the tail end of the outer edge of the seam line; wherein one part of the area of the bottom wall and / or the peripheral wall of the container body is covered with an airtight film layer, all edge joint positions are covered with airtight film layers, and at least one part of the area of the bottom wall and / or the peripheral wall is not covered with an airtight film layer. According to the high-airtightness food container, the airtightness of the food container can be guaranteed, the weight ratio of the airtight film layer is reduced, the food container is more environmentally friendly, and a user can use the food container conveniently.

Description

Technical Field

[0001] The invention relates to the technical field of tableware, in particular to a high-airtightness food container made of paper. Background Art

[0002] Traditional disposable food containers are mostly made of plastic. Since plastic food containers are not easy to degrade and cause plastic pollution, disposable food containers made of environmentally friendly materials such as paper are becoming more and more popular.

[0003] Usually, disposable food containers made of paper are made by folding a flat piece of kraft paper or cardboard, where a seam line is formed and an airflow channel is formed. The gas inside the food container can leak to the outside through the seam, and the external gas can also flow into the inside of the food container through the seam, which results in poor airtightness of the food container.

[0004] In order to solve the airtightness problem of food containers, it is usually necessary to cover the surface of the food container with an airtight film layer. A multi-layer composite film is used. A film layer with a very small thickness is made of PP, PE, PET, PA, EVOH and other materials. The airtight film layer is attached to the inner surface of the food container by traditional vacuum forming, especially at the seams. The seams are sealed by the airtight film layer to reduce the gas flow inside and outside the food container.

[0005] However, since the airtight film layer is made of materials such as PP, PE, PET, PA, EVOH, etc., and not made of environmentally friendly materials such as paper, if the thickness of the airtight film layer is large, the plastic content of the food container will be high. For example, the weight of the airtight film layer accounts for more than 20% of the total weight of the food container, which does not meet the requirements of environmental protection. For example, according to EU legal requirements, if the proportion of plastic in a food container exceeds 10%, the user needs to tear off the airtight film layer made of plastic from the food container when discarding the food container, and the airtight film layer and the container body made of paper need to be recycled separately. Obviously, if the weight of the airtight film layer is large, it will not only fail to meet the requirements of environmental protection, but will also bring great inconvenience to the user.

[0006] In addition, before the airtight film layer is attached to the inner surface of the food container by the traditional vacuum forming method, a whole piece of plastic film with a large area, a large thickness (usually more than 0.02 mm) and a certain hardness needs to be heated and softened, and then the softened plastic film is spread on the food container, and finally the softened plastic film is attached to the food container by vacuum forming. However, the above process consumes more energy and takes a long time to heat the plastic film, which increases the production time of the food container and leads to a higher production cost of the food container.

[0007] If the weight of the airtight film layer is reduced as a proportion of the total weight of the food container, the usual practice is to reduce the thickness of the airtight film layer. However, if the thickness of the airtight film layer is too small, on the one hand, it will affect the sealing performance of the airtight film layer, resulting in poor sealing performance of the food container, which is difficult to meet the requirements of food sealing storage; on the other hand, an airtight film layer with too small thickness will bring great difficulties to processing, especially the airtight film layer is difficult to form, or it is difficult to cover the surface of the food container with a very small thickness of the airtight film layer intact, and the airtight film layer is prone to damage during the processing. If the airtight film layer is damaged during the processing, it will affect the sealing performance of the food container. Summary of the invention

[0008] The object of the present invention is to provide a highly airtight food container with good sealing performance and a very low weight ratio of the airtight film layer.

[0009] To achieve the purpose of the present invention, the high-airtightness food container provided by the present invention includes a container body, which is formed by folding a sheet of paper material, and the upper end of the container body is open, the container body has a bottom wall and a peripheral wall adjacent to the bottom wall, at least one seam line is formed on the bottom wall or the peripheral wall, the seam line is located at the seam formed by overlapping at least two layers of sheet paper material, and the outer end of the seam line forms an edge seam position; wherein, a portion of the bottom wall and / or the peripheral wall of the container body is covered with an airtight film layer, all edge seams are covered with an airtight film layer, and at least a portion of the bottom wall and / or the peripheral wall is not covered with an airtight film layer.

[0010] As can be seen from the above scheme, the bottom wall and / or the peripheral wall of the food container are covered with an airtight film layer, and the edge seam is sealed by the airtight film layer, so as to prevent air leakage at the edge seam of the food container, thereby effectively improving the airtightness of the food container. In addition, since the bottom wall and / or the peripheral wall of the food container are not covered with the airtight film layer in all areas, that is, the airtight film layer only covers a part of the bottom wall and / or the peripheral wall, and covers all the edge seams, the coverage area of ​​the airtight film layer on the food container is small, especially for the case where the bottom wall is relatively flat, the area of ​​the bottom wall covered by the airtight film layer is small, thereby reducing the area of ​​the airtight film layer, thereby reducing the weight of the airtight film layer, so that the weight of the airtight film layer accounts for a lower proportion of the total weight of the entire food container, meeting the requirements of environmental protection performance, and the user does not need to tear off the airtight film layer after use, which is convenient for the user. The present invention can meet the airtightness requirements of the food container under the premise of meeting the requirements of environmental protection and recycling and reuse, and does not require the user to tear off the airtight film layer before discarding the food container, which is convenient for users to use.

[0011] In addition, since the airtight film layer covers all edge seams, the airtightness of the food container can be ensured, and since the area of ​​the airtight film layer is small, a thicker airtight film layer can be used under the same weight, that is, avoid using a very thin airtight film layer to cover the food container. The thicker airtight film layer has good sealing performance and can maintain good airtightness of the food container.

[0012] A preferred solution is that the bottom wall is formed by a sheet of paper material, and the edge seam is formed only on the peripheral wall; the area of ​​the bottom wall covered with the airtight film layer does not exceed 10% to 50% of the area of ​​the bottom wall.

[0013] It can be seen that since the bottom wall of the food container is formed by a sheet of paper material, that is, no seam line is formed on the bottom wall, the bottom wall itself is not easy to cause gas leakage. In this way, the area of ​​the airtight film layer covering the bottom wall can be made very small. For example, the area of ​​the airtight film layer is set to be less than 50% of the area of ​​the bottom wall, or even less than 10%, which can effectively reduce the use of the airtight film layer.

[0014] A further solution is that the weight of the airtight film layer does not exceed 12% of the total weight of the high airtight food container. Preferably, the weight of the airtight film layer does not exceed 5% of the total weight of the high airtight food container.

[0015] It can be seen that the weight of the airtight film layer accounts for a very low proportion of the total weight of the high airtight food container, especially less than 5%, so that the plastic content of the food container is very low. After the food container is used up, the user does not need to tear off the airtight film layer and discard it, which is convenient for the user.

[0016] A further solution is that a flange portion is formed on the peripheral wall near the open end, the flange portion is formed on the upper edge of the peripheral wall, and the flange portion is covered with an airtight film layer.

[0017] It can be seen that a flange portion is formed at the upper edge of the peripheral wall, and the airtight film layer is also covered on the flange portion, so that the flange portion has higher strength. When the peripheral wall is squeezed, the flange portion can provide a greater force to the peripheral wall, making the peripheral wall less likely to deform, thereby improving the strength of the peripheral wall of the food container.

[0018] A further solution is that an end of the flange portion away from the peripheral wall is further provided with a folded edge portion, and the free end of the folded edge portion extends toward the bottom wall. Preferably, the folded edge portion is covered with an airtight film layer.

[0019] It can be seen that a folding portion is also provided at the outer end of the peripheral wall of the flange portion, and the folding portion is also covered with an airtight film layer. The strength of the folding portion is improved by the airtight film layer, and the strength of the peripheral wall is further improved. In addition, after the folding portion is provided, the degree of distortion and deformation of the food container can be reduced, which is conducive to maintaining a good surface flatness of the folding portion. When the food container is used later, it may be necessary to buckle a covering film or a paper cover or a plastic cover on the food container. Since the folding portion is provided, the deformation of the folding portion can be avoided when the cover is buckled later. In addition, the folding portion can be provided to avoid the situation where the flange portion rebounds due to the flange position under different temperature and humidity environments, especially to avoid the situation where the flange portion is severely deformed under the condition of large temperature difference. For example, the rebound angle of the folding portion can be made less than 10°, which can avoid the situation where the actual shape of the food container used is inconsistent with the shape after molding due to the rebound of the folding portion.

[0020] A further solution is that the airtight film layer is a plastic film or a degradable film that is tightly attached to the bottom wall and / or the peripheral wall.

[0021] It can be seen that the airtight film layer can be a plastic film or a degradable film made of PP, PE, PET, PA, EVOH and other materials, and the film is adsorbed on the surface of the peripheral wall and the bottom wall through a hot pressing process. In this way, a suitable production process can be selected according to the specific shape and material of the food container.

[0022] Another high-airtightness food container provided by the present invention includes a container body, which is formed by folding a sheet of paper material, and the upper end of the container body is open, the container body has a bottom wall and a peripheral wall adjacent to the bottom wall, at least one seam line is formed on the bottom wall or the peripheral wall, the seam line is located at the seam formed by overlapping at least two layers of sheet paper material, and the outer end of the seam line forms an edge seam position; wherein, a portion of the bottom wall and / or peripheral wall of the container body is covered with an airtight film layer, and the weight of the airtight film layer accounts for no more than 12% of the total weight of the high-airtightness food container.

[0023] As can be seen from the above scheme, since the airtight film layer covers all the edge seams of the food container, all the seams are sealed calmly, avoiding air leakage at the edge seams and affecting the sealing performance of the food container. In addition, since only a part of the peripheral wall and the bottom wall of the food container are covered with the airtight film layer, the area of ​​the airtight film layer is very small, so that the weight of the airtight film layer accounts for no more than 12% of the total weight of the high airtight food container, so that the food container can meet the requirements of environmental protection, and the user does not need to tear off the airtight film layer and discard it after use, which is convenient for the user.

[0024] A preferred solution is that the airtight film layer is a plastic film or a degradable film that is tightly attached to the bottom wall and / or the peripheral wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural diagram of a highly airtight food container embodiment of the present invention from a first viewing angle.

[0026] Figure 2 It is a structural diagram of a highly airtight food container embodiment of the present invention from a second viewing angle.

[0027] Figure 3 It is a structural diagram of the unfolded kraft paper used to make the high airtight food container embodiment of the present invention.

[0028] Figure 4 yes Figure 3 A partial enlarged view of .

[0029] Figure 5 It is a structural diagram of an embodiment of a highly airtight food container of the present invention from a third viewing angle.

[0030] Figure 6 It is a structural diagram of a highly airtight food container embodiment of the present invention from a fourth viewing angle.

[0031] Figure 7 It is a cross-sectional view of an embodiment of a highly airtight food container of the present invention.

[0032] The present invention is further described below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0033] The highly airtight food container of the present invention is mainly made of environmentally friendly materials such as paper. For example, the food container has a container body, which is made of a piece of kraft paper or cardboard folded on an integral basis, and an airtight film layer is covered on the peripheral wall and bottom wall of the container body. The airtight film layer can be made of materials such as PP, PE, PET, PA or EVOH. The present invention can ensure the airtightness of the food container through a special structure, and can also reduce the amount of airtight film layer used, thereby reducing the weight of the airtight film layer in the total weight of the entire food container.

[0034] See also Figure 1 and Figure 2 The food container 10 has a container body 11, which is formed by folding a piece of kraft paper. The kraft paper before folding is shaped as follows: Figure 3 The container body 11 has a flat bottom wall 12, and a peripheral wall is formed on the bottom wall 12. In this embodiment, the container body 11 has eight peripheral walls, such as Figure 1As shown in the clockwise direction, the peripheral walls 21, 22, 23, 24, 25, 26, 27, 28 are included in sequence, wherein the peripheral wall 21 is adjacent to the peripheral walls 22 and 28, the peripheral wall 22 is adjacent to the peripheral walls 21 and 23, and so on. Moreover, the lower edge of each peripheral wall 21, 22, 23, 24, 25, 26, 27, 28 is adjacent to the bottom wall 12.

[0035] The container body 11 is a container with an open top, that is, the end of the container body 11 away from the bottom wall 12 is open, and no sealing component is provided. When in use, the user puts food into the container body, and then uses a sealing film or the like to seal the open end of the container body 11. When the user needs to take out the food, the sealing film or the like needs to be torn off from the open end of the container body 11 first.

[0036] See also Figure 3 The container body 11 is formed by folding a whole piece of kraft paper. Preferably, a layer of waterproof coating is coated on the surface of the kraft paper itself, for example, a plant fiber waterproof coating is coated on one surface of the kraft paper. These waterproof coatings make the kraft paper itself have certain waterproof properties.

[0037] A plurality of folding marks are arranged on the kraft paper, for example, a folding mark 401 is arranged, and the folding mark 401 is located between the bottom wall 12 and the peripheral wall 21. After the user folds the kraft paper along the folding mark 401, the bottom wall 12 and the peripheral wall 21 of the container body 11 will be formed. Similarly, by folding along the folding mark 402, the peripheral wall 22 of the container body can be formed, and by folding along the folding mark 403, the peripheral wall 23 of the container body 11 can be formed. It can be seen that since the bottom wall 12 of the container body 11 and each peripheral wall 21, 22, 23, 24, 25, 26, 27, 28 are formed by folding, no seam line is formed between the bottom wall 12 and each peripheral wall 21, 22, 23, 24, 25, 26, 27, 28, and no seam line is formed on the bottom wall 12 itself, so the bottom wall 12 itself has good sealing performance.

[0038] A folding portion is formed at one corner of the kraft paper 40, and the folding portion includes a sheet 41. The sheet 41 forms the peripheral wall 26 of the container body 11 after being folded. In addition, folding pieces 42 and 44 are respectively provided on both sides of the sheet 41, and a sheet 43 is further provided on one side of the folding piece 42. The sheet 43 forms the peripheral wall 27 after being folded. When the kraft paper 40 is folded, the folding piece 42 will be folded between the sheet 41 and the sheet 43, that is, on the container body 11 after being folded, and the folding piece 42 will be clamped between the sheet 41 and the sheet 43, as shown in FIG. Figure 5 shown.

[0039] In this way, a seam is formed at the connection between the sheet body 41 and the folded sheet 42, such as Figure 6As shown, a seam line 31 is formed between the peripheral wall 26 and the peripheral wall 27. The seam line 31 is a gap formed by folding the sheet body 41 and the folding sheet 42, that is, a seam line is formed where two or more sheets of paper material overlap. The seam line 31 extends from the bottom wall 12 to the upper edge of the peripheral wall 27, see Figure 4 , an opening 49 is formed between the sheet 43 and the adjacent sheet 48, so the position of the seam line 31 close to the opening 49 is a position that is prone to air leakage, and this position is the outer edge end of the seam line 31, that is, the position close to the edge of the sheet paper material, which is called the edge seam position. Due to the existence of the edge seam position, the air inside the container body 11 can pass through the edge seam position and communicate with the outside air.

[0040] Correspondingly, a seam line 32 is also formed between the peripheral wall 25 and the peripheral wall 26. It can be understood that in this embodiment, a seam line is formed between two adjacent peripheral walls, and an edge seam position is also formed at the outer end of the seam line. In addition, all seams are formed on the peripheral walls, and no seams are formed on the bottom wall 12, and no seams are formed between each peripheral wall and the bottom wall.

[0041] Since air flow will be formed inside and outside the container body 11 at the edge seams, for this reason, the present embodiment needs to cover the container body 11 with an airtight film layer, and all edge seams are covered by the airtight film layer to ensure the sealing of the food container 10. In the present embodiment, the airtight film layer is a thin film covering a local area on the bottom wall 12 and / or the peripheral wall, for example, the film is a plastic film or a degradable film made of materials such as PP, PE, PET, PA or EVOH, wherein the degradable film can be PLA, PBS, PVOH or PCL, etc., and the airtight film layer should use a food-grade film to meet the requirements of food safety.

[0042] like Figure 2 As shown, the airtight film layers 60 and 62 are only adsorbed on a part of the bottom wall 12, such as the two ends along the length direction of the bottom wall 12. Therefore, one end of the airtight film layer 60 extends to the fold mark between the bottom wall 12 and the peripheral wall 27, and the other end of the airtight film layer 60 forms an edge 61 on the bottom wall 12. Correspondingly, one end of the airtight film layer 62 extends to the fold mark between the bottom wall 12 and the peripheral wall 23, and the other end of the airtight film layer 62 forms an edge 63 on the bottom wall 12. The area between the edge 61 and the edge 63 is not covered by the airtight film layer, that is, the area between the edge 61 and the edge 63 of the bottom wall 12 is not covered by the airtight film layer.

[0043] In this way, the airtight film layer does not cover the entire bottom wall 12, but only covers a part of the area. Preferably, the area of ​​the bottom wall 12 covered with the airtight film layer does not exceed 50% of the area of ​​the bottom wall 12, and further, the area of ​​the bottom wall 12 covered with the airtight film layer does not exceed 10% of the area of ​​the bottom wall 12. Since there is no seam line or edge seam on the bottom wall 12, and the kraft paper 40 itself has good airtightness, even if there is a large area on the bottom wall 12 that is not covered by the airtight film layer, it will not affect the overall sealing performance of the food container 10.

[0044] Since all edge seams are formed on the peripheral wall, in this embodiment, the airtight film layer will cover all the peripheral walls, thereby ensuring that all edge seams will be covered by the airtight film layer, and utilizing the good sealing performance of the airtight film layer to avoid air leakage inside and outside the food container 10, thereby ensuring the sealing performance of the food container 10. Preferably, the weight of the airtight film layer accounts for less than 12% of the total weight of the food container 10, and further, the weight of the airtight film layer accounts for less than 5% of the total weight of the food container 10. In this way, the weight of the airtight film layer is very small, which can meet the requirements of environmental protection on the one hand, and on the other hand, after the food container 10 is used, the user does not need to tear off the airtight film layer and then discard the food container 10, which can facilitate the use of the user.

[0045] In order to verify the sealing performance of the food container 10, the water vapor transmission rate (WVTR), oxygen transmission rate (OTR) and nitrogen transmission rate (NTR) of this embodiment are tested. The experimental data in Table 1 are experimental data after the food container is covered with an airtight film layer and the open end of the food container is sealed with the sealing film, wherein the material of the airtight film layer is PLA with a thickness of 0.06 mm.

[0046] Table 1 Experimental data on sealing performance of food containers

[0047] As can be seen from Table 1, the food container using the present invention has good sealing performance and can meet the requirements of food sealing and preservation. After many experiments, the inventor made an airtight film layer made of PP, PE, PET, PA or EVOH, and the water vapor transmission rate was 0.05 g / m 2 / day to 30 g / m 2 / day, oxygen transmission rate is 0.05 cc / m 2 / day to 50000 cc / m 2 / day, nitrogen permeability is 0.5 cc / m 2 / day to 5000 cc / m 2 / days.

[0048] In other embodiments, the airtight film layer may only cover a portion of the peripheral wall, rather than covering all of the peripheral wall, so that the area of ​​the airtight film layer can be further reduced, making the weight of the airtight film layer lower. Of course, in order to ensure that the airtight film layer can effectively seal all seams, a certain distance needs to be maintained between the edge of the airtight film layer and the edge seam position, for example, the distance between the edge of the airtight film layer and the edge seam position is not less than 5 mm.

[0049] During the use of the food container 10, the user often holds the peripheral wall. Since the peripheral wall made of paper is soft in texture, it is easy for the peripheral wall to be severely deformed when the user holds the peripheral wall. If the user holds with great force, the peripheral wall may be damaged and the entire food container 10 may be damaged, affecting the use of the food container 10.

[0050] In order to improve the strength of the peripheral wall, a flange portion 51 is provided on the upper edge of the peripheral wall. Figure 7 The flange portion 51 is formed at a position of the peripheral wall 27 close to the open end, that is, at the upper edge of the peripheral wall 27 away from the bottom wall 12. The flange portion 51 extends from the upper edge of the peripheral wall 27 in a radially outward direction of the food container 10, that is, it is flanged outward. Figure 3 A flange piece 46 is provided at one end of the sheet body 43 away from the bottom wall 12 , and a folding mark 406 is provided between the flange piece 46 and the sheet body 43 . After the flange piece 46 and the sheet body 43 are folded along the folding mark 406 , the flange piece 46 will form a flange portion 51 .

[0051] In this embodiment, the upper edge of each peripheral wall is connected with a flange portion, so the flange portion surrounds the upper edge of the entire peripheral wall, that is, the flange portion is arranged around the open end of the food container 10. Further, the flange portion is also covered with an airtight film layer, preferably, the airtight film layer is formed on the flange portion by hot pressing, so that the hardness of the flange portion is enhanced by the hot pressed airtight film layer, thereby enhancing the strength of the peripheral wall, and the peripheral wall is not easily collapsed or damaged when the user holds the peripheral wall.

[0052] In addition, a folding portion 52 is also provided at the free end of the flange portion 51. Figure 7As shown, one end of the folded edge portion 52 is connected to the flange portion 51, and the free end of the folded edge portion 52 extends in a direction close to the bottom wall 12. In this embodiment, the folded edge portion 52 extends in a direction substantially perpendicular to the bottom wall 12. In other embodiments, the extension direction of the folded edge portion 52 may also be inclined with respect to the bottom wall 12. For example, from a direction close to the flange portion 51 to a direction away from the flange portion 51, the folded edge portion 52 extends obliquely from a direction close to the peripheral wall 27 to a direction away from the peripheral wall 27. Figure 3 An overhanging piece 47 is provided at one end of the flange piece 46 away from the sheet body 43 , and a folding mark 407 is provided between the flange piece 46 and the overhanging piece 47 . After the overhanging piece 47 and the flange piece 46 are folded along the folding mark 407 , the overhanging piece 47 will form a folded edge portion 52 .

[0053] In addition, the folded edge portion 52 may also be covered with an airtight film layer. Preferably, the airtight film layer is formed on the folded edge portion 52 by hot pressing. The method of forming the airtight film layer by hot pressing can improve the strength of the folded edge portion 52, and then increase the ability of the flange portion 52 to resist deformation. Since the flange portion 52 is connected to the upper edge of the peripheral wall 27, this design can further improve the strength of the peripheral wall 27. Even if the user holds the peripheral wall 27, it is not easy to cause the peripheral wall to collapse, so that the food container 10 can maintain its original shape.

[0054] It can be seen that the food container provided by the present invention forms an airtight film layer on a local area of ​​the bottom wall and / or the peripheral wall, rather than forming the airtight film layer on the entire bottom wall and / or the peripheral wall, so as to reduce the area of ​​the airtight film layer, and thus reduce the weight of the airtight film layer to the weight of the entire food container. On the one hand, the amount of the airtight film layer can be reduced, making the food container more environmentally friendly. On the other hand, while meeting the requirements of environmental protection performance, it avoids the inconvenience caused to the user by the need to tear off the airtight film layer after using the food container.

[0055] Finally, it should be emphasized that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A highly airtight food container, comprising: A container body, wherein the container body is formed by folding a sheet of paper material, and the upper end of the container body is open, and the container body has a bottom wall and a peripheral wall adjacent to the bottom wall, and at least one seam line is formed on the bottom wall or the peripheral wall, and the seam line is located at a seam formed by overlapping at least two layers of the sheet of paper material, and the outer end of the seam line forms an edge seam position; Features: A portion of the bottom wall and / or the peripheral wall of the container body is covered with an airtight film layer, all the edge seams are covered with the airtight film layer, and at least a portion of the bottom wall and / or the peripheral wall is not covered with the airtight film layer.

2. The highly airtight food container according to claim 1, characterized in that: The bottom wall is formed by a piece of the sheet-like paper material, and the edge seam is only formed on the peripheral wall; The area of ​​the bottom wall covered with the airtight film layer does not exceed 10% to 50% of the area of ​​the bottom wall.

3. The highly airtight food container according to claim 1 or 2, characterized in that: The weight of the airtight film layer accounts for no more than 12% of the total weight of the high-airtight food container.

4. The highly airtight food container according to claim 3, characterized in that: The weight of the airtight film layer does not exceed 5% of the total weight of the high-airtight food container.

5. The highly airtight food container according to claim 1 or 2, characterized in that: A flange portion is formed on the peripheral wall near the open end, the flange portion is formed on the upper edge of the peripheral wall, and the flange portion is covered with the airtight film layer.

6. The highly airtight food container according to claim 5, characterized in that: An end of the flange portion away from the peripheral wall is further provided with a folded edge portion, and a free end of the folded edge portion extends toward a direction close to the bottom wall.

7. The highly airtight food container according to claim 6, characterized in that: The folded edge portion is covered with the airtight film layer.

8. The highly airtight food container according to claim 1 or 2, characterized in that: The airtight film layer is a plastic film or a degradable film that is tightly attached to the bottom wall and / or the peripheral wall.

9. A highly airtight food container, comprising: A container body, wherein the container body is formed by folding a sheet of paper material, and the upper end of the container body is open, and the container body has a bottom wall and a peripheral wall adjacent to the bottom wall, and at least one seam line is formed on the bottom wall or the peripheral wall, and the seam line is located at a seam formed by overlapping at least two layers of the sheet of paper material, and the outer end of the seam line forms an edge seam position; Features: A portion of the bottom wall and / or the peripheral wall of the container body is covered with an airtight film layer, and the weight of the airtight film layer accounts for no more than 12% of the total weight of the high-airtightness food container.

10. The highly airtight food container according to claim 9, characterized in that: The airtight film layer is a plastic film or a degradable film that is tightly attached to the bottom wall and / or the peripheral wall.

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