Food can container

Abstract

To provide a food can container capable of suppressing a leaching of micro-plastics into food.SOLUTION: A food can container comprises a can body in which food is packed, a can bottom attached to a bottom side of the can body, and a can lid that seals an inside of the can body formed by the can body and the can bottom. An inner surface of at least one of the can body, can bottom, and can lid that is exposed to food is made of stainless steel.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a food can container in which food is packed. [Background technology]

[0002] Food cans are used for long-term storage of foods containing moisture. One known food can is the one described in Patent Document 1. The food can in Patent Document 1 allows food to be stored for a long period of time by filling it with food and sealing it. Furthermore, the food can in Patent Document 1 has a polyester film laminated to the inner surface of the material, thereby preventing the flavor of the food inside the food can and preventing corrosion of the material of the food can. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-210363 Summary of the Invention [Problem to be solved by the invention]

[0004] In food cans such as those described in Patent Document 1, the laminated polyester film is thought to be hydrolyzed by the moisture in the food. When hydrolyzed, microplastics and nanoplastics are leached into the food. If food is stored in a food can for a long time, more microplastics (or nanoplastics) are thought to leach into the food. Therefore, by eating food packed in a food can, the human body is exposed to more microplastics (or nanoplastics).

[0005] Therefore, an object of the present invention is to provide a food can container that can prevent microplastics from leaching into food. [Means for solving the problem]

[0006] The food can container of the present invention comprises a can body in which food is packed, a can bottom attached to the bottom side of the can body, and a can lid that seals the inside of the can body formed by the can body and the can bottom, and the inner surface of at least one of the can body, the can bottom, and the can lid that is exposed to food is made of stainless steel.

[0007] According to the present invention, the inner surface of at least one of the can body, can bottom, and can lid that is exposed to food is made of stainless steel. Therefore, the inner surface is corrosion-resistant, and corrosion of the inner surface can be suppressed. Furthermore, because the inner surface is made of stainless steel, exposure of plastic to food within the food can container can be suppressed. Therefore, hydrolysis of plastic within the food can container can be suppressed. This suppresses leaching of microplastics into food.

[0008] In the above invention, the pitting corrosion index of the stainless steel constituting the inner surface is preferably 15 or more.

[0009] According to the above configuration, the pitting corrosion index of the stainless steel constituting the inner surface is 15 or more. Therefore, the inner surface has high corrosion resistance against food, which makes it possible to prevent food from being stored for a long period of time.

[0010] In the above invention, the pitting corrosion index of the stainless steel constituting the inner surface is preferably 22 or more.

[0011] According to the above configuration, the stainless steel constituting the inner surface has a pitting corrosion index of 22 or more. Therefore, the inner surface has higher corrosion resistance against food. This makes it possible to prevent food from being stored for a longer period of time. Furthermore, by using stainless steel with a pitting corrosion index of 22 or more, it is possible to prevent crevice corrosion, for example, at the joint between the can body and the can lid or the joint between the can body and the can bottom.

[0012] In the above invention, the pitting corrosion index of the stainless steel on the inner surface is preferably 30 or more.

[0013] According to the above configuration, the pitting corrosion index of the stainless steel that forms the inner surface is 30 or more. Therefore, the inner surface is highly resistant to corrosion by food, and the food can be stored for a longer period of time.

[0014] In the above invention, the stainless steel constituting the inner surface is preferably a duplex stainless steel.

[0015] According to the above-mentioned configuration, the stainless steel constituting the inner surface is a duplex stainless steel. Therefore, it is possible to ensure ease of processing while having higher corrosion resistance. This makes it possible to easily manufacture a food can container with higher corrosion resistance.

[0016] In the above invention, the stainless steel constituting the inner surface is preferably an austenitic stainless steel.

[0017] According to the above-mentioned configuration, the stainless steel constituting the inner surface is an austenitic stainless steel, which ensures corrosion resistance and ease of processing, thereby facilitating the manufacture of stainless steel food cans.

[0018] In the above invention, the stainless steel constituting the inner surface is preferably a ferritic stainless steel.

[0019] According to the above structure, the stainless steel constituting the inner surface is a ferritic stainless steel, which makes it possible to easily manufacture a corrosion-resistant food can container.

[0020] In the above invention, it is preferable that the product further comprises an identification mark indicating that the product is made of recyclable stainless steel.

[0021] According to the above configuration, the food can container further comprises an identification mark indicating that it is made of recyclable stainless steel, making it easy to identify that the food can container is made of recyclable stainless steel. [Effects of the Invention]

[0022] According to the present invention, it is possible to prevent microplastics from leaching into food. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a perspective view showing a food can container according to an embodiment of the present invention. [Figure 2] 1 is a cross-sectional view showing a food can container according to an embodiment of the present invention. [Figure 3] 1 is a graph showing the PREN of each type of stainless steel. DETAILED DESCRIPTION OF THE INVENTION

[0024] A food can container (hereinafter referred to as "can container") 1 according to an embodiment of the present invention will be described below with reference to the drawings. Note that the concept of direction used in the following description is used for convenience of explanation and does not limit the orientation of the configuration of the invention to that direction. Furthermore, the can container 1 described below is merely one embodiment of the present invention. Therefore, the present invention is not limited to the embodiment, and additions, deletions, and modifications are possible within the scope of the invention.

[0025] <Canned food container> The can container 1 shown in FIG. 1 is a container used for long-term storage of food F. More specifically, food F is packed and sealed inside the can container 1. The food F inside the can container 1 is subjected to heat sterilization or heat-pressure sterilization. This allows the food F to be stored for a long period of time in the can container 1. The food F may be, for example, a processed food that contains mainly water and solid substances, but may also be a liquid such as soup that does not contain solid substances. The can container 1 is made of corrosion-resistant stainless steel. This prevents corrosion of the inner surfaces 11a-13a of the can container 1 due to chloride or acidic substances contained in the food F during long-term storage. The configuration of the can container 1 will be described in more detail below.

[0026] As shown in Figure 2, the can container 1 comprises a can body 11, a can bottom 12, and a can lid 13. More specifically, the can container 1 further comprises an identification mark 14. In this embodiment, the can container 1 is a three-piece can, in which the can body 11 and the can bottom 12 are formed separately and are combined to form the can body 15. However, the can container 1 is not necessarily limited to a three-piece can, and may be a can container of another type, such as a two-piece can in which the can body 11 and the can bottom 12 are integrally formed to form the can body 15.

[0027] The can body 11 is a cylindrical member made of stainless steel. More specifically, the can body 11 is formed by rolling a stainless steel strip into a cylindrical shape and welding both circumferential ends. When the can body 11 is formed integrally with the can bottom 12, it is formed by deep drawing a stainless steel plate. The thickness of the can body 11 is, for example, 0.1 mm to 0.8 mm. However, the thickness of the can body 11 is not limited to the above-mentioned range. In this embodiment, the inner surface 11a of the can body 11 exposed to the food F is made of stainless steel. More specifically, the can body 11 is filled with food F, and the inner surface 11a of the can body 11 is exposed to the food F. The stainless steel is exposed on the inner surface 11a of the can body 11. Although not shown, the outer surface 11b of the can body 11 may be decorated by painting or laminating a resin film. However, the outer surface 11b of the can body 11 does not necessarily need to be decorated, and the stainless steel may be exposed.

[0028] In this embodiment, the can body 11 is made of SUS329J4L, which is a duplex stainless steel (i.e., a ferritic-austenitic stainless steel). Alternatively, the can body 11 may be made of the following stainless steels. Specifically, the stainless steel used to make the can body 11 may be, for example, a ferritic stainless steel, an austenitic stainless steel, or a duplex stainless steel. Examples of ferritic stainless steels that may be used include SUH409, SUH409L, SUS430, SUS430LX, SUS430J1L, SUS434, SUS436, SUS436L, SUS436J1L, SUS443J1, SUS444, SUS445J1, SUS445J2, SUS447J1, and SUSXM27 (all JIS standards), as well as Sea-Cure (trademark).

[0029] Examples of austenitic stainless steel include SUS201, SUS202, SUS301, SUS301L, SUS301J1, SUS302, SUS302B, SUS303, SUS303Cu, SUS304, SUS304Cu, SUS304L, SUS304N1, SUS304N2, SUS304LN, SUS304J1, SUS304J2, SUS304J3, SUS305, SUS309S, SUS310S, SUS312L, and SUS315J. 1. SUS315J2, SUS316, SUS316L, SUS316N, SUS316LN, SUS316Ti, SUS316J1, SUS316J1L, SUS316F, SUS317, SUS317L, SUS317LN, SUS317J1, SUS317J2, SUS317LMN, SUS321, SUS347, SUS384, SUS836L, SUS890L, SUS904, SUSXM7, and SUSXM15J1 (all JIS standards), etc., are used.

[0030] Furthermore, examples of duplex stainless steel that can be used include SUS323L (designation: 2304), SUS329J1, SUS329J4L, SUS329J3L (designation: 2205), and SUS327L1 (designation: 2507) (all JIS standards). Note that the ferritic stainless steel, austenitic stainless steel, and duplex stainless steel described above are merely examples, and other stainless steels may also be used.

[0031] Furthermore, stainless steel having a pitting corrosion index (abbreviated as PREN) of 15 or more is used for the can body 11. More preferably, stainless steel having a PREN of 22 or more is used for the can body 11. Even more preferably, stainless steel having a PREN of 30 or more is used for the can body 11. PREN is calculated, for example, as follows. PREN=Weight%Cr+3.3×Weight%Mo+16×Weight%N…(1) Here, wt% Cr is the weight % of chromium contained in the stainless steel, wt% Mo is the weight % of molybdenum contained in the stainless steel, and wt% N is the weight % of nitrogen contained in the stainless steel.

[0032] The PREN is not limited to the value calculated by the above-mentioned formula (1). For example, when the stainless steel contains tungsten and manganese, the PREN may be calculated by the following formula (2), or by other formulas. PREN=Weight%Cr+3.3×{Weight%Mo+0.5weight%W} +16×Weight%N−Weight%Mn…(2) Here, wt% W is the weight % of tungsten contained in the stainless steel, and wt% Mn is the weight % of manganese contained in the stainless steel.

[0033] For example, stainless steels with a PREN of 30 or more include duplex stainless steel, austenitic stainless steel, and ferritic stainless steel. As shown in Figure 3, general-purpose duplex stainless steels such as SUS329J4L and SUS329J3L and super duplex stainless steel SUS327L1 are used as duplex stainless steels with a PREN of 30 or more. As austenitic stainless steels with a PREN of 30 or more, for example, SUS317LMN and SUS904 are used. Furthermore, Sea-Cure (trademark) is used as a ferritic stainless steel with a PREN of 30 or more.

[0034] Other examples of austenitic stainless steels with a PREN of 30 or higher include SUS312L, SUS836L, and SUS890L. Also, SUS447J1 is used as a ferritic stainless steel with a PREN of 30 or higher. However, the materials used as duplex stainless steels, austenitic stainless steels, and ferritic stainless steels with a PREN of 30 or higher are not limited to the materials mentioned above, and any stainless steels may be used as long as the components contained in each stainless steel result in a PREN of 30 or higher.

[0035] Furthermore, in addition to the aforementioned stainless steels with a PREN of 30 or more, the following duplex stainless steels, austenitic stainless steels, and ferritic stainless steels are used as stainless steels with a PREN of 22 or more. That is, as shown in FIG. 3, SUS323L is used as lean duplex stainless steel with a PREN of 22 or more. SUS316 and SUS317L are used as austenitic stainless steels with a PREN of 22 or more. SUS444, for example, is used as ferritic stainless steel with a PREN of 22 or more.

[0036] Other examples of duplex stainless steels with a PREN of 22 or higher include SUS821L1 and SUS323L. Examples of austenitic stainless steels with a PREN of 22 or higher include SUS309S, SUS310S, SUS316F, SUS316L, SUS316N, SUS316LN, SUS316Ti, SUS317J1, SUS317J2, and SUS317LN. Examples of ferritic stainless steels with a PREN of 22 or higher include SUS445J1, SUS445J2, and SUSXM27. However, the materials used as duplex stainless steels, austenitic stainless steels, and ferritic stainless steels with a PREN of 22 or higher are not limited to the above-mentioned materials, and any stainless steels may be used as long as the components contained in each stainless steel provide a PREN of 22 or higher.

[0037] Furthermore, in addition to the above-mentioned stainless steels with a PREN of 22 or more, the following austenitic stainless steels and ferritic stainless steels are used as stainless steels with a PREN of 15 or more. That is, SUS304 is used as an austenitic stainless steel with a PREN of 15 or more, as shown in Figure 3. Furthermore, SUS430, SUS434, and SUS436 are used as ferritic stainless steels with a PREN of 15 or more, for example.

[0038] Other austenitic stainless steels with a PREN of 15 or more that can be used include SUS201, SUS202, SUS205, SUS301, SUS301J1, SUS301L, SUS302, SUS302B, SUS303, SUS303Cu, SUS303Se, SUS304Cu, SUS304J1, SUS304J2, SUS304J3, SUS304L, SUS304LN, SUS304N1, SUS304N2, SUS305, SUS315J1, SUS315J2, SUS316J1, SUS316J1L, SUS321, SUS347, SUS384, SUSXM15J1, and SUSXM7. Examples of ferritic stainless steels with a PREN of 15 or higher include SUS429, SUS430F, SUS430LX, SUS430J1L, SUS436J1L, SUS436L, and SUS443J1. However, the materials used as duplex stainless steels, austenitic stainless steels, and ferritic stainless steels with a PREN of 15 or higher are not limited to the above-mentioned materials, and any stainless steels may be used as long as the components contained in each stainless steel result in a PREN of 15 or higher.

[0039] The can bottom 12 is a disk-shaped member made of stainless steel. More specifically, the can bottom 12 is formed by stamping a stainless steel plate into a disk. Alternatively, the can bottom 12 may be formed into a disk shape by cutting the stainless steel plate. The thickness of the can bottom 12 is, for example, 0.1 mm to 0.8 mm. However, the thickness of the can bottom 12 is not limited to the above-mentioned range. The can bottom 12 is attached to the can body 11 so as to close an opening on one axial side of the can body 11 (i.e., the bottom side of the can body 11). More specifically, as shown in FIG. 2 , the can bottom 12 is seamed around one end of the can body 11 along the entire circumferential direction. As a result, the can bottom 12 closes the bottom side of the can body 11 and forms the bottom of the canned container 1 (i.e., the bottom of the can body 15). As described above, the can bottom 12 may be integrally formed with the can body 11 by additionally drawing a stainless steel plate.

[0040] In the can bottom 12 configured in this manner, the inner surface 12a faces the food F in the can container 1, and is exposed to the food F. The inner surface 12a of the can bottom 12 exposed to the food F is made of stainless steel. Explaining in more detail, the food F is packed into the can container 1 as described above, and the inner surface 11a of the can bottom 12 is exposed to the food F. The stainless steel is exposed on the inner surface 12a of the can bottom 12. Note that in this embodiment, the outer surface 12b of the can bottom 12 is also exposed stainless steel. However, the outer surface 12b of the can bottom 12 may be decorated by applying paint or laminating a resin film, for example.

[0041] The can bottom 12 is made of, for example, the same type of stainless steel as the can body 11. That is, in this embodiment, the can bottom 12 is made of SUS329J4L, a duplex stainless steel. However, the can bottom 12 may be made of a different stainless steel from the can body 11. Furthermore, like the can body 11, the can bottom 12 may be made of the following stainless steel. That is, the stainless steel making up the can bottom 12 may be, for example, ferritic stainless steel, austenitic stainless steel, or duplex stainless steel. Examples of ferritic stainless steel include SUH409, SUS430, SUS434, SUS436, SUS444, and Sea-Cure™. Examples of austenitic stainless steel include SUS304, SUS316, SUS317L, SUS317LMN, and SUS904. Examples of duplex stainless steel include SUS323L, SUS329J4L, SUS329J3L, and SUS327L1.

[0042] Similarly to the can body 11, the can bottom 12 is made of stainless steel with a PREN of 15 or higher. More preferably, the can bottom 12 is made of stainless steel with a PREN of 22 or higher. Even more preferably, the can bottom 12 is made of stainless steel with a PREN of 30 or higher. As shown in FIG. 3 , examples of stainless steel with a PREN of 30 or higher include duplex stainless steels such as SUS329J4L, SUS329J3L, and SUS327L1, and austenitic stainless steels such as SUS317LMN and SUS904. Examples of stainless steel with a PREN of 22 or higher include, in addition to the aforementioned stainless steels with a PREN of 30 or higher, SUS323L, SUS317L, SUS316, and SUS444. Examples of stainless steel with a PREN of 15 or higher include, in addition to the aforementioned stainless steels with a PREN of 22 or higher, SUS304, SUS430, SUS434, and SUS436. Although not described in detail, the can bottom 12 may be made of any of the various stainless steel materials listed as other examples for the can body 11 .

[0043] The can lid 13 is a disk-shaped member made of stainless steel. More specifically, the can lid 13 is formed by stamping a stainless steel plate into a disk. Alternatively, the can lid 13 may be formed into a disk shape by cutting the stainless steel plate. The thickness of the can lid 13 is, for example, 0.1 mm or more and 0.8 mm or less. However, the thickness of the can lid 13 is not limited to the above-mentioned range. The can lid 13 is attached to the can body 11 so as to close the opening on the other axial side of the can body 11 (i.e., the ceiling side of the can body 11). More specifically, the can lid 13 is seamed around the other end of the can body 11 around the entire circumferential direction, as shown in FIG. 2 . As a result, the can lid 13 closes the ceiling side of the can body 11 and forms the ceiling portion of the canned container 1.

[0044] In the can lid 13 configured in this manner, the inner surface 13a faces the food F in the can container 1, and the inner surface 13a is exposed to the food F. The inner surface 13a of the can lid 13, which is exposed to the food F, is also made of stainless steel. Explaining in more detail, the food F is packed into the can container 1 as described above, and the inner surface 11a of the can lid 13 is exposed to the food F. The stainless steel is exposed on the inner surface 13a of the can lid 13. Note that in this embodiment, the outer surface 13b of the can lid 13 is also exposed stainless steel. However, the outer surface 13b of the can lid 13 may be decorated by applying paint or laminating a resin film, for example.

[0045] The can lid 13 is made of, for example, the same type of stainless steel as the can body 11. That is, in this embodiment, the can lid 13 is made of SUS329J4L, which is a duplex stainless steel. However, the can lid 13 may be made of a different stainless steel from the can body 11. Also, like the can body 11, the can lid 13 may be made of the following stainless steel. That is, the stainless steel constituting the can lid 13 may be, for example, ferritic stainless steel, austenitic stainless steel, or duplex stainless steel. Examples of ferritic stainless steel include SUH409, SUS430, SUS434, SUS436, SUS444, and Sea-Cure™. Examples of austenitic stainless steel include SUS304, SUS316, SUS317L, SUS317LMN, and SUS904. Examples of duplex stainless steel include SUS323L, SUS329J4L, SUS329J3L, and SUS327L1.

[0046] Similarly to the can body 11, the can lid 13 is made of stainless steel with a PREN of 15 or higher. More preferably, the can lid 13 is made of stainless steel with a PREN of 22 or higher. Even more preferably, the can lid 13 is made of stainless steel with a PREN of 30 or higher. Examples of stainless steel with a PREN of 30 or higher include duplex stainless steels such as SUS329J4L, SUS329J3L, and SUS327L1, as well as austenitic stainless steels such as SUS317LMN and SUS904. Examples of stainless steel with a PREN of 22 or higher include the aforementioned stainless steels with a PREN of 30 or higher, as well as SUS323L, SUS317L, SUS316, SUS430, SUS434, SUS436, and SUS444. Examples of stainless steel with a PREN of 15 or higher include the aforementioned stainless steels with a PREN of 22 or higher, as well as SUS304, SUS430, SUS434, and SUS436. Although not described in detail, the can lid 13 may also be made of any of the various stainless steel materials listed as other examples for the can body 11.

[0047] In this embodiment, the can body 11 and the can lid 13 are made of SUS329J4L, a stainless steel with a PREN of 22 or higher. This makes it possible to prevent crevice corrosion from occurring in the joint between the can body 11 and the can lid 13 (i.e., the seamed portion 13c). As described above, the can bottom 12 is also made of SUS329J4L, a stainless steel with a PREN of 22 or higher, in this embodiment. This makes it possible to prevent crevice corrosion from occurring in the joint between the can body 11 and the can bottom 12 (i.e., the seamed portion 12c).

[0048] The identification mark 14 indicates that the can body 11 and the can lid 13 are made of recyclable stainless steel. In this embodiment, the identification mark 14 is a predetermined triangular recess. Such an identification mark 14 is particularly useful when a recycler sorts out can containers 1 made of stainless steel when collecting can containers 1. Note that the identification mark 14 does not necessarily have to be a recess, and may be a predetermined mark formed by painting or laminating on the outer surfaces 11b to 13b, as long as it indicates that the can container 1 contains recyclable stainless steel.

[0049] In the can container 1 configured as described above, the can body 11 is formed by rolling a stainless steel strip into a cylindrical shape and welding both circumferential ends. The disk-shaped can bottom 12 is then punched out of a stainless steel plate using a press. The can bottom 12 is then seamed around one end of the can body 11 over the entire circumference. As a result, one end portion of the can body 11, i.e., the bottom of the can body 11 in this embodiment, is sealed by the can bottom 12, and a bottomed, cylindrical can body 15 is formed.

[0050] The food F is filled into the can body 15 through an opening on one axial side, and then the opening of the can body 15 is closed with the can lid 13. More specifically, like the can bottom 12, the cylindrical can lid 13 is formed by stamping out from a stainless steel plate using a press process. The can lid 13 is then seamed around the entire circumference of the open end of the can body 15 (i.e., the other axial end of the can body 11). As a result, the opening of the can body 15 is closed with the can lid 13, and the food F inside the can body 15 is sealed. In this way, a canned food container 1 is produced that is filled with the food F and sealed. The canned food container 1 is then subjected to heat sterilization or heat-pressure sterilization to enable long-term storage.

[0051] In the can container 1 of this embodiment, the inner surfaces 11a-13a of the can body 11, can bottom 12, and can lid 13 that are exposed to the food F are made of stainless steel. Therefore, the inner surfaces 11a-13a are corrosion-resistant, and corrosion of the inner surfaces 11a-13a can be prevented. Furthermore, because the inner surfaces 11a-13a are made of stainless steel, exposure of plastic to the food F within the can container 1 can be prevented. Therefore, hydrolysis of plastic within the can container 1 can be prevented. This prevents microplastics from leaching into the food F. In particular, when a conventional can container is heated over an open flame, hydrolysis of the plastic in the laminate film accelerates, resulting in a large amount of microplastics leaching into the food F. However, the can container 1 can prevent this from happening.

[0052] In addition, in canning container 1 of this embodiment, the PREN of the stainless steel constituting inner surfaces 11a to 13a is 15 or more. Therefore, inner surfaces 11a to 13a have high corrosion resistance against food F. This makes it possible to prevent food F from being stored for a long period of time.

[0053] Furthermore, in canned food container 1 of this embodiment, the PREN of the stainless steel constituting inner surfaces 11a-13a is 22 or higher. Therefore, inner surfaces 11a-13a have higher corrosion resistance to food F. This makes it possible to prevent food F from being stored for a longer period of time. Furthermore, by using stainless steel with a PREN of 22 or higher, it is possible to prevent crevice corrosion from occurring, for example, in seamed portions 12c, 13c.

[0054] Furthermore, in the canning container 1 of this embodiment, the PREN of the stainless steel constituting the inner surfaces 11a-13a is 30 or more. Therefore, the inner surfaces 11a-13a are extremely unlikely to be corroded by the food F, and the inner surfaces 11a-13a have even higher corrosion resistance against the food F. This makes it possible to prevent the food F from being stored for an even longer period of time.

[0055] Furthermore, in the canning container 1 of this embodiment, the stainless steel that forms the inner surfaces 11a to 13a is a duplex stainless steel. This ensures high corrosion resistance while ensuring ease of processing. This makes it easy to manufacture a canning container 1 with high corrosion resistance.

[0056] Furthermore, in the can container 1 of this embodiment, the stainless steel constituting the inner surfaces 11a to 13a may be austenitic stainless steel. This ensures corrosion resistance and ease of processing. This allows the can container 1 made of stainless steel to be easily manufactured.

[0057] In the canning container 1 of this embodiment, the stainless steel that forms the inner surface may be ferritic stainless steel, which makes it possible to easily manufacture a corrosion-resistant canning container for food.

[0058] Furthermore, the can container 1 of this embodiment further includes an identification mark 14 indicating that it is made of recyclable stainless steel, making it easy to identify that the can container 1 contains recyclable stainless steel.

[0059] [Other embodiments] The stainless steels constituting the can body 11, can bottom 12, and can lid 13 of the canned container 1 of this embodiment are not limited to the stainless steels described above, but may be other stainless steels. For example, the austenitic stainless steels are not limited to the above-described SUS304, SUS316, SUS317L, SUS317LNM, and SUS904, but may be other austenitic stainless steels. The same applies to ferritic stainless steels and duplex stainless steels.

[0060] Furthermore, stainless steel with a PREN of 30 or more is not limited to the above-mentioned types of duplex stainless steel and austenitic stainless steel, but may be other types of duplex stainless steel and austenitic stainless steel. Furthermore, stainless steel with a PREN of 30 or more is not limited to duplex stainless steel and austenitic stainless steel, but may also be ferritic stainless steel, such as Sea-Cure (trademark). The same applies to stainless steel with a PREN of 22 or more and stainless steel with a PREN of 15 or more.

[0061] Furthermore, the can container 1 of this embodiment is not limited to a three-piece can as described above, but may also be a two-piece can. The shape of the can container 1 is not limited to a cylindrical shape as described above, but may be a rectangular or triangular tubular shape, as long as the food F can be packed inside the can container 1. Furthermore, all of the inner surfaces 11a-13a of the can body 11, can bottom 12, and can lid 13 do not necessarily have to be made of stainless steel; at least one of the three inner surfaces 11a-13a may be made of stainless steel. In other words, the inner surface 11a of the can body 11 may be made of stainless steel, and the inner surfaces 12a, 13a of the can bottom 12 and can lid 13 may be laminated or painted. The can body 11, can bottom 12, and can lid 13 may each be made of a different stainless steel. [Explanation of symbols]

[0062] 1 canned food container 11 Can body 11a Inner surface 12 Can bottom 12a Inner surface 13 Can lid 13a Inner surface 14 Distinguishing marks 15 can body F Food

Claims

1. a can body in which food is packed; a can bottom provided on the bottom side of the can body; a can lid that seals the inside of a can body formed by the can body and the can bottom, A food can container, wherein the inner surface of at least one of the can body, the can bottom, and the can lid that is exposed to food is made of stainless steel.

2. 2. The food can container according to claim 1, wherein the stainless steel constituting the inner surface has a pitting corrosion index of 15 or more.

3. 3. The food can container according to claim 2, wherein the stainless steel constituting the inner surface has a pitting corrosion index of 22 or more.

4. 4. The food can container of claim 3, wherein the pitting index of the stainless steel on the inner surface is 30 or more.

5. 2. The food can container according to claim 1, wherein the stainless steel constituting the inner surface is a duplex stainless steel.

6. 2. The food can container according to claim 1, wherein the stainless steel constituting the inner surface is an austenitic stainless steel.

7. 2. The food can container according to claim 1, wherein the stainless steel constituting the inner surface is a ferritic stainless steel.

8. 10. The food can container of claim 1, further comprising an identification mark indicating that the container is made of recyclable stainless steel.

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