Metal three-piece can directly heat-sealed by aluminum film

Abstract

The utility model relates to the technical field of food packaging, in particular to a metal three-piece can directly heat-sealed by an aluminum film, which comprises a can body provided with an accommodating cavity for receiving contents and the aluminum film connected with the top end of the can body and used for sealing the accommodating cavity. The top end of the tank body is provided with a heat-seal connecting part which is bent and folded towards the outer surface of the tank body and used for being attached to the aluminum film, and the tank body and the heat-seal connecting part are in arc transition. According to the utility model, the heat-seal connecting part which is bent, folded and extended towards the outer surface of the tank body is designed at the top end of the tank body, and the heat-seal connecting part is attached to the aluminum film and seals the tank body, so that the manufacturing of a top cover is omitted, and the heat-seal connecting part and the accommodating cavity are designed to be in arc transition; therefore, no concave-convex structure exists between the containing cavity and the heat-sealing connecting part, and it is ensured that when the content is poured out, the content can be completely poured out from the containing cavity through the heat-sealing connecting part.

Description

Technical Field

[0001] The utility model relates to the technical field of food packaging, in particular to a metal three-piece can directly heat-sealed by an aluminum film. Background Art

[0002] Metal three-piece cans are a common metal packaging container, which is mainly composed of three pieces of metal sheets: one can body, one can top and one can bottom. Metal three-piece cans can provide good protection for the contents, prevent the contents from being affected by external factors such as light, oxygen, moisture, and extend the shelf life of the product. At the same time, the recycling rate of metal three-piece cans is high, which is beneficial to environmental protection. In addition, the appearance of metal three-piece cans can also beautified through printing, painting and other processes to enhance the market competitiveness of the product. Metal three-piece cans have been widely used in food, beverage, chemical and other industries due to their simple structure, relatively low manufacturing cost, good sealing performance, strong corrosion resistance, good processability and recyclability.

[0003] At present, the production of three-piece metal cans basically adopts the process of welding the can body and rolling the top cover. During the production process, the top and bottom covers need to be made separately and then rolled with the can body, and there are many production processes. Taking the application of three-piece cans of milk powder or condiments as an example, the top cover is generally an easy-tear cover or a full-open cover. The easy-tear cover consists of a ring cover and aluminum foil. When the aluminum foil is peeled off, the ring cover still remains on the can body, but because it needs to reserve a certain contact surface for thermal lamination with the aluminum foil, the part that is combined with the can body protrudes from the inside of the can body, making it inconvenient to pour out the contents, and it is easy for the contents to remain on the protruding surface, which seriously affects the consumer's experience; if the can body is equipped with a full-open cover, because there is a sharp cut after the full-open cover is opened, it is easy to cause hand scratches when obtaining the contents.

[0004] Therefore, it is necessary to design a metal three-piece can with an aluminum film that is easy to tear and a can body that has no sharp cuts after opening the lid, is not easy to be scratched, and can pour out the contents 100%. Utility Model Content

[0005] The utility model is developed to solve the above-mentioned problems, and aims to provide a metal three-piece can directly heat-sealed with an aluminum film, which is easy to tear and has no sharp cuts on the can body after the cover is opened, and is not easy to be scratched, and a production method thereof. This not only saves the original process of making the top cover separately, but also reduces the manufacturing cost. After the aluminum film is peeled off, the contents will not remain on the can body, which is convenient for 100% complete removal of the contents, and there is no safety problem in use, which can significantly improve the consumer experience and solve the above-mentioned technical problems.

[0006] The utility model provides a metal three-piece can directly heat-sealed with an aluminum film, the metal three-piece can comprising a can body provided with a containing cavity for receiving contents and an aluminum film connected to the top of the can body and sealing the containing cavity, the top of the can body is provided with a heat-sealed connecting portion that is bent and folded toward the outer surface of the can body and is used to fit with the aluminum film, and there is an arc transition between the can body and the heat-sealed connecting portion.

[0007] The utility model designs a heat-sealed connecting part on the top of the can body that is bent, folded and extended toward the outer surface of the can body, and uses the heat-sealed connecting part to adhere to the aluminum film and seal the can body, thereby not only eliminating the need for making a top cover, but also designing an arc transition between the heat-sealed connecting part and the accommodating cavity so that there is no concave-convex structure between the accommodating cavity and the heat-sealed connecting part, thereby ensuring that when pouring the contents, the contents can be completely poured out from the accommodating cavity through the heat-sealed connecting part.

[0008] Furthermore, since the heat-sealed connection portion is bent and folded and extended toward the outer surface of the can body, after the aluminum film is torn off, there is no sharp cut or sharp angle between the heat-sealed connection portion and the can body, thereby avoiding the problem of easy scratches on users when using traditional three-piece cans.

[0009] In some embodiments of the present invention, the heat-sealed connection portion includes a heat-sealed section connected to the top of the can body and heat-sealed with the aluminum film to seal the can body, and an anti-cut section connected to the heat-sealed section and bent toward the outer surface of the can body.

[0010] The heat-sealing section of the utility model can not only be used to connect with the aluminum film, but also transition with the can body in an arc shape, so that the content in the can body can flow out along the heat-sealing section, thereby realizing complete dumping of the content.

[0011] Furthermore, the outer end of the heat-sealing section is connected to an anti-cut section to prevent the outer end of the heat-sealing section from tilting up to form a sharp edge after the aluminum film is torn off, thereby preventing users from being cut.

[0012] Furthermore, the anti-cut section is bent and folded toward the outer surface of the can body, and the edge of the aluminum film can be bent and folded along the anti-cut section toward the outer surface of the can body, thereby preventing water vapor and dust from entering the gap between the connecting surfaces of the aluminum film and the heat sealing section and affecting the fit between the aluminum film and the heat sealing section.

[0013] In some embodiments of the present invention, the angle between the heat-sealing section and the outer surface of the can body is 75°~90°.

[0014] When the angle between the heat-sealing section and the outer surface of the can body is 75° to 90°, it can ensure that the contact area between the aluminum film and the heat-sealing section is large enough when the aluminum film is pasted, thereby improving the sealing degree of the aluminum film to the can body.

[0015] Further, when the aluminum film needs to be torn off, since the aluminum film will exert an adhesive force towards the inner surface of the can body on the heat-sealing section, the anti-cut section connected to the heat-sealing section is designed to fold towards the outer surface of the can body and the included angle between the heat-sealing section and the outer surface of the can body is 75°-90°, which can make the structure of the heat-sealing section more stable and prevent the heat-sealing section from being torn and deformed inwardly easily by the adhesive force.

[0016] In some embodiments of the present invention, the width of the heat-sealing section is 2-3 mm.

[0017] In the embodiment, the heat-sealing section is designed to be 2-3 mm to provide sufficient adhesion space for the aluminum film.

[0018] In some embodiments of the present invention, the aluminum film includes an aluminum foil layer, a protective layer coated on the outer surface of the aluminum foil layer facing away from the accommodating cavity, and a hot melt adhesive layer coated on the inner surface of the aluminum foil layer facing the accommodating cavity for fitting with the heat-sealing section.

[0019] In the embodiment, the protective layer can prevent the aluminum film from being accidentally punctured, and at the same time, patterns can be designed on the protective layer for aesthetic needs.

[0020] In the embodiment, the aluminum film is adhered to the can body by the hot melt adhesive layer using a hot lamination process.

[0021] In some embodiments of the present invention, the thickness of the aluminum film is greater than or equal to 0.09 mm.

[0022] In the embodiment, the thickness of the aluminum film is controlled to be greater than or equal to 0.09 mm to avoid the aluminum film being easily broken when tearing off the aluminum film and unable to be taken off completely.

[0023] By implementing the above technical solutions, the present invention has the following beneficial effects:

[0024] 1. The present invention designs a heat-sealing connection part that bends, folds and extends towards the outer surface of the can body at the top of the can body, and uses the heat-sealing connection part to fit with the aluminum film and seal the can body, thereby not only saving the production of the top cover, but also making an arc transition between the heat-sealing connection part and the accommodating cavity, so that there is no concave-convex structure between the accommodating cavity and the heat-sealing connection part, ensuring that when pouring the content, the content can pass through the heat-sealing connection part from the accommodating cavity and be completely poured out.

[0025] 2. The present invention bends, folds and extends the heat-sealing connection part towards the outer surface of the can body, so that after tearing off the aluminum film, there is no sharp cut or sharp included angle between the heat-sealing connection part and the can body, avoiding the problem that the traditional three-piece can is easy to scratch the user during use.

[0026] 3. The anti-cutting section of the present utility model is bent and folded towards the outer surface of the can body, and the edge of the aluminum film can be bent and folded along the anti-cutting section towards the outer surface of the can body, thereby preventing water vapor and dust from entering the gap between the connection surface of the aluminum film and the heat-sealing section and affecting the adhesion between the aluminum film and the heat-sealing section.

[0027] 4. The included angle between the heat-sealing section of the present utility model and the outer surface of the can body is 75° - 90°, which can ensure that the contact area between the aluminum film and the heat-sealing section is large enough when the aluminum film is pasted, and improve the sealing degree of the aluminum film to the can body.

[0028] 5. The present utility model is designed with the anti-cutting section folded towards the outer surface of the can body and the included angle between the heat-sealing section and the outer surface of the can body being 75° - 90°, which can make the structure of the heat-sealing section more stable and prevent the heat-sealing section from deforming inwardly easily with the tearing of the aluminum film. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of a three-piece metal can provided by the present utility model;

[0030] Figure 2 It is a cross-sectional view of a three-piece metal can provided by the present utility model and a partial enlarged view of the heat-sealing connection part;

[0031] Figure 3 It is a cross-sectional view of the aluminum film provided by the present utility model;

[0032] Figure 4 It is a process flow chart of manufacturing a three-piece metal can provided by the present utility model;

[0033] Figure 5 It is a schematic structural diagram of a three-piece metal can provided by the present utility model;

[0034] Figure 6 It is a schematic structural diagram of a three-piece metal can provided by the present utility model;

[0035] Figure 7 It is a schematic structural diagram of a three-piece metal can provided by the present utility model.

[0036] In the figure, each label represents:

[0037] 1. Can body, 11. Heat-sealing connection part, 111. Heat-sealing section, 112. Anti-cutting section; 2. Aluminum film, 21. Aluminum foil layer, 22. Protective layer, 23. Hot melt adhesive layer, 3. Opening tab. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] In order to make the technical means, creative features, achieved purposes and functions of the present utility model easy to understand, the present utility model will be specifically described below in conjunction with the embodiments and the drawings.

[0039] Such as Figure 1As shown in the figure, this embodiment provides a three-piece metal can with direct heat-sealing of an aluminum film. The three-piece metal can includes a can body 1 having a receiving cavity for receiving contents and an aluminum film 2 connected to the top end of the can body 1 and sealing the receiving cavity. The top end of the can body 1 is provided with a heat-sealing connection portion 11 that is bent and folded toward the outer surface of the can body 1 and is used for fitting with the aluminum film 2, and there is an arc transition between the can body 1 and the heat-sealing connection portion 11.

[0040] As Figures 1 - 2 shown in the figure, in this embodiment, by designing a heat-sealing connection portion 11 that is bent and folded and extended toward the outer surface of the can body 1 at the top end of the can body 1, and using the heat-sealing connection portion 11 to fit with the aluminum film 2 and seal the can body 1, not only the production of the top cover is omitted, but also by designing an arc transition between the heat-sealing connection portion 11 and the receiving cavity, there is no concave-convex structure between the receiving cavity and the heat-sealing connection portion 11, ensuring that when pouring the contents, the contents can pass through the heat-sealing connection portion 11 from the receiving cavity and be completely poured out.

[0041] Furthermore, since the heat-sealing connection portion 11 is bent and folded and extended toward the outer surface of the can body 1, after tearing off the aluminum film 2, there is no sharp cut or sharp angle between the heat-sealing connection portion 11 and the can body 1, avoiding the problem that traditional three-piece cans are easy to scratch users during use.

[0042] As Figure 2 shown in the figure, in some embodiments of the present invention, the heat-sealing connection portion 11 includes a heat-sealing section 111 connected to the top end of the can body 1 and heat-sealed and fitted with the aluminum film 2 to seal the can body 1, and a cut-resistant section 112 connected to the heat-sealing section 111 and bent and folded toward the outer surface of the can body 1.

[0043] The heat-sealing section 111 in the embodiment can not only be used to connect with the aluminum film 2, but also has an arc transition with the can body 1, so that the contents in the can body 1 can flow out along the heat-sealing section 111 to achieve complete pouring of the contents.

[0044] Furthermore, a cut-resistant section 112 is connected to the outer end of the heat-sealing section 111 to prevent the outer end of the heat-sealing section 111 from warping to form a sharp edge after the aluminum film 2 is torn off, avoiding cutting the user.

[0045] Furthermore, the cut-resistant section 112 is bent and folded toward the outer surface of the can body 1, and the edge of the aluminum film 2 can be bent and folded along the cut-resistant section 112 toward the outer surface of the can body 1, thereby preventing moisture and dust from entering the gap between the connection surface of the aluminum film 2 and the heat-sealing section 111 and affecting the fitting degree of the aluminum film 2 and the heat-sealing section 111.

[0046] Furthermore, the cut-resistant section 112 is bent and folded toward the outer surface of the can body 1, which can avoid the direct friction between the edge of the cut-resistant section 112 and the adjacent can body 1 during storage and transportation, resulting in wear of the appearance of the can body 1 and causing quality defects.

[0047] As Figure 1 shown, an opening tab 3 for facilitating pulling by the user to tear off the aluminum film 2 is provided at the edge of the aluminum film 2, and the opening tab 3 can be bent and folded towards the outer surface of the tank body 1 along the anti-cutting section 112.

[0048] In some embodiments of the present invention, the included angle between the heat-sealing section 111 and the outer surface of the tank body 1 is 75°-90°.

[0049] When the included angle between the heat-sealing section 111 and the outer surface of the tank body 1 is 75°-90°, it can ensure that the contact area between the aluminum film 2 and the heat-sealing section 111 is large enough during the pasting of the aluminum film 2, which is convenient for the heat lamination of the aluminum film 2 during sealing and the placement of the opening tab 3, and improves the sealing degree of the aluminum film 2 to the tank body 1.

[0050] Furthermore, when the aluminum film 2 needs to be torn off, since the aluminum film 2 will apply an adhesive force towards the inner surface of the tank body 1 to the heat-sealing section 111, the anti-cutting section 112 connected to the heat-sealing section 111 is designed to be folded towards the outer surface of the tank body 1 and the included angle between the heat-sealing section 111 and the outer surface of the tank body 1 is 75°-90°, which can make the structure of the heat-sealing section 111 more stable and make the heat-sealing section 111 not easily torn and deformed inwardly with the adhesive force.

[0051] In some embodiments of the present invention, the width of the heat-sealing section 111 is 2-3 mm.

[0052] In the embodiment, the heat-sealing section 111 is designed to be 2-3 mm to provide enough adhesion space for the aluminum film 2, so as to ensure the sealing width of the aluminum film 2 and meet the requirements of the sealing strength and tightness during use.

[0053] As Figure 3 shown, in some embodiments of the present invention, the aluminum film 2 includes an aluminum foil layer 21, a protective layer 22 coated on the outer surface of the aluminum foil layer 21 facing away from the accommodating cavity, and a hot-melt adhesive layer 23 coated on the inner surface of the aluminum foil layer 21 facing the accommodating cavity for fitting with the heat-sealing section 111.

[0054] In the embodiment, the protective layer 22 can prevent the aluminum film 2 from being accidentally punctured and prevent the aluminum foil layer 21 from being oxidized. At the same time, patterns can also be designed on the protective layer 22 for aesthetic requirements. In the embodiment, in order to increase the strength of the aluminum film 2, generally, an embossing process can be carried out on the surface of the protective layer 22 of the aluminum film 2 to match personalized patterns. Furthermore, in the embodiment, a high-strength aluminum film 2 can also be used or the strength of the aluminum film 2 can be increased by using the aluminum film 2 printing process.

[0055] In the embodiment, the aluminum film 2 is adhered to the tank body 1 by the hot-melt adhesive layer 23 using a heat lamination process.

[0056] In some embodiments of the present utility model, the thickness of the aluminum film 2 is greater than or equal to 0.09 mm.

[0057] In the embodiment, the thickness of the aluminum film 2 is controlled to be greater than or equal to 0.09 mm to avoid the aluminum film 2 being too thin and easily broken when the aluminum film 2 is torn off, making it impossible to be taken off completely.

[0058] As Figure 4 shown, for the production of the metal three-piece can, the cut circular sheet needs to be rolled into a cylindrical shape by a rolling machine and welded to form the can body 1. Then, the can body 1 is flanged and curled to form the heat-sealing connection part 11. The aluminum film 2 and the heat-sealing connection part 11 are heat-compound connected for sealing, and packaging, transportation, filling, bottom-sealing, and packaging processes are carried out according to actual needs.

[0059] Furthermore, since the top of the can body 1 has been sealed by the aluminum film 2, whether to buckle the glue cap can be selected according to actual needs. In the embodiment, the metal three-piece can prepared by heat-sealing and bonding the aluminum film 2 and the can body 1 has high pressure resistance strength, does not leak under the pressure test condition of 0.05 Mpa for 2 minutes, meets the use conditions of filling and nitrogen filling for freshness preservation, and can be used under plateau conditions.

[0060] Generally, the aluminum film 2 can be sliced online using a roll film or pre-sliced offline, and is provided with an opening tab 3. During heat compounding, according to the usage requirements, the cover surface can be flat-folded and pressed, or side-folded and pressed parallel to the can body 1 and the cover surface. As Figures 5 - 7 shown, the opening tab 3 can be folded outwards along the edge of the heat-sealing connection part 11 to the lower edge of the anti-cutting section 112, which can reduce the risk of the opening tab 3 being damaged; or it can be folded towards the protective layer 22 of the aluminum film 2 to facilitate the later matching use of the glue cap.

[0061] The above are only the preferred embodiments of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present utility model, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present utility model.

Claims

1. A three-piece metal can directly heat-sealed with an aluminum film, the three-piece metal can comprising a can body (1) provided with a receiving cavity for receiving contents and an aluminum film (2) connected to the top of the can body (1) and sealing the receiving cavity, characterized in that: The top end of the can body (1) is provided with a heat-sealed connecting portion (11) which is bent and folded in a direction toward the outer surface of the can body (1) and is used to fit with the aluminum film (2), and there is an arc transition between the can body (1) and the heat-sealed connecting portion (11).

2. The metal three-piece can according to claim 1, characterized in that: The heat-sealed connecting portion (11) comprises a heat-sealed section (111) connected to the top end of the can body (1) and bonded to the aluminum film (2) by heat sealing to seal the can body (1), and a cut-resistant section (112) connected to the heat-sealed section (111) and bent and folded toward the outer surface of the can body (1).

3. The metal three-piece can according to claim 2, characterized in that: The included angle between the heat sealing section (111) and the outer surface of the can body (1) is 75° to 90°.

4. The metal three-piece can according to claim 3, characterized in that: The width of the heat sealing section (111) is 2-3 mm.

5. The metal three-piece can according to claim 4, characterized in that: The aluminum film (2) comprises an aluminum foil layer (21), a protective layer (22) coated on the outer surface of the aluminum foil layer (21) facing away from the accommodating cavity, and a hot melt adhesive layer (23) coated on the inner surface of the aluminum foil layer (21) facing the accommodating cavity for bonding with the heat sealing section (111).

6. The metal three-piece can according to claim 5, characterized in that: The thickness of the aluminum film (2) is greater than or equal to 0.09 mm.

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