Can container, and method for manufacturing can container
The can container design incorporates an EB coating layer with electron beam-curable resin to protect printed images, addressing the lack of effective protection and safety concerns in existing technologies, achieving enhanced durability and safety.
Patent Information
- Application Number
- JP2023105979
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-06-28
- Publication Date
- 2025-01-17
AI Technical Summary
Existing can containers lack effective protection for printed images on their surfaces, which are prone to physical and chemical damage, and current protective coatings may pose safety risks due to the use of UV-curable resins.
A can container design featuring an EB coating layer made of electron beam-curable resin, optionally combined with UV and printing layers, providing enhanced protection while ensuring safety by using electron beam-curable resins that are safer for human contact.
The EB coating layer effectively protects the printed images from damage and ensures safety by using electron beam-curable resins that are safer than UV-curable alternatives, enhancing the overall durability and safety of the can container.
Smart Images

Figure 2025005697000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a can container and a method for manufacturing a can container. [Background technology]
[0002] It is known that in can containers such as beverage cans, a protective layer is formed on the surface of the can body to protect the printing on the surface. For example, Patent Document 1 states, "In the image forming process in the printer (PR), after the image is formed by the inkjet head 300, paint is applied to the outer peripheral surface 19 of the can body to form a protective layer (overcoat layer) (paragraph 0034)." Cited Document 2 describes a method for manufacturing an organic resin-coated metal sheet. [Prior art document] [Patent documents] [Patent Document 1] JP 2019-025521 A [Patent Document 2] JP 2004-25640 A Summary of the Invention
[0003] In a first aspect of the present invention, there is provided a can container including a can body and an EB coating layer. The can body may be cylindrical. The EB coating layer may be formed on the outer peripheral surface of the can body and may contain an electron beam curable resin.
[0004] In the above, the EB coating layer may be formed only on a part of the outer circumferential surface of the can body.
[0005] In the above, the EB coating layer may be formed on the outer circumferential surface of the can body in a stripe pattern extending in the horizontal direction of the can body.
[0006] In the above, the can body may have a reduced diameter portion whose one end is reduced in diameter, and a can body portion. The EB coating layer may be provided on at least the outer circumferential surface of the reduced diameter portion.
[0007] In the above, the thickness of the EB coating layer may be 0.5 to 20 μm.
[0008] In the above, the EB coating layer may contain a resin in which an oligomer selected from polyester acrylate, epoxy acrylate, polyurethane acrylate, silicon acrylate, melamine acrylate, and polyether acrylate is polymerized.
[0009] In the above, the can container may further include a printed layer between the can body and the EB coating layer.
[0010] In the above, the can body may have a can body and a resin film covering the inner surface and / or the outer surface of the can body.
[0011] In the above, the can container may further include a UV coating layer. The UV coating layer may be formed on the outer peripheral surface of the can body and may contain an ultraviolet curable resin.
[0012] In the above, the UV coating layer may be at least partially provided between the can body and the EB coating layer.
[0013] In the above, the can container may further include a printed layer between the can body and the EB coating layer.
[0014] In the above, at least a portion of the printed layer may be provided between the can body and the UV coating layer.
[0015] In a second aspect of the present invention, there is provided a method for manufacturing a can container, comprising an EB coating step and an EB curing step. In the EB coating step, an electron beam curable resin composition may be coated on the outer peripheral surface of a cylindrical can body. In the EB curing step, the electron beam curable resin composition may be irradiated with an electron beam to be cured, and an EB coating layer containing the electron beam curable resin may be formed on the outer peripheral surface of the can body.
[0016] In the above, the method for manufacturing a can container may include a printing step. The printing step may be performed before the EB coating step, and may be a step of forming a printed layer on the outer peripheral surface of the cylindrical can body. The EB coating step may be performed by forming an electron beam curable resin composition on the printed layer.
[0017] In the above, the intensity of the electron beam in the EB curing step may be 2 to 100 kGy.
[0018] In the above, the coating thickness of the electron beam curable resin composition in the EB coating step may be 0.5 to 20 μm.
[0019] In a third aspect of the present invention, there is provided a method for manufacturing a can container, comprising an EB coating step and an EB curing step. In the EB coating step, an electron beam curable resin composition may be applied in parallel to the outer peripheral surfaces of a plurality of cylindrical can bodies by a plurality of EB coating devices. In the EB curing step, the electron beam curable resin composition may be irradiated with an electron beam to be cured, and an EB coating layer containing the electron beam curable resin may be formed on the outer peripheral surface of the can body.
[0020] In the above, the method for manufacturing a can container may include an inkjet printing step. The inkjet printing step may be performed before the EB coating step. The inkjet printing step may be performed by forming inkjet printed layers in parallel on the outer peripheral surface of the cylindrical can body using a plurality of inkjet printing devices. The EB coating step may be performed by forming an electron beam curable resin composition on the printed layer.
[0021] In the above, the method for manufacturing a can container may include a can body supplying step, in which a plurality of cylindrical can bodies are supplied to both an inkjet printing step and a plate printing step in which a plate-based printed layer is formed on an outer peripheral surface of the cylindrical can bodies by plate printing.
[0022] In the above, the method for manufacturing a can container may include a diameter reducing step, in which a common diameter reducing device may be used to reduce the diameter of a part of the can body before being supplied to the inkjet printing step and the can body that has been subjected to the plate printing step to form a reduced diameter portion.
[0023] In the above, the method for manufacturing a can container may include a plate-based printing step. The plate-based printing step may be performed before the inkjet printing step. In the plate-based printing step, a plate-based printed layer may be formed on an outer peripheral surface of the cylindrical can body by plate-based printing.
[0024] In the above, the method for manufacturing a can container may include a storage step. The storage step may be performed before the can body supply step. In the storage step, a plurality of cylindrical can bodies may be stored before the can body supply step.
[0025] In the above, the EB coating device may be an inkjet printing device.
[0026] The above summary of the invention does not list all of the features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]
[0027] [Figure 1] 1 shows an example of an overall view of a can container 10 in this embodiment. [Diagram 2] 1 shows an example of a cross section of a can container 10 in this embodiment. [Diagram 3] 2 shows a modified cross section of the can container 10 in this embodiment. [Figure 4] 2 shows a modified cross section of the can container 10 in this embodiment. [Diagram 5] 2 shows a modified cross section of the can container 10 in this embodiment. [Figure 6] 2 shows a modified cross section of the can container 10 in this embodiment. [Figure 7] 2 shows a modified cross section of the can container 10 in this embodiment. [Figure 8A] An example of a flow of a method for manufacturing the can container 10 in this embodiment will be shown. [Figure 8B] An example of a flow of a method for manufacturing the can container 10 in this embodiment will be shown. [Figure 9] An example of a sub-flow (wet molding) of S100 in FIG. 8 is shown. [Figure 10] Another example of the subflow (dry molding) of S100 in FIG. 8 is shown. [Figure 11A] An example of parallelization of the manufacturing method according to the present embodiment will be described. [Figure 11B] An example of parallelization of the manufacturing method according to the present embodiment will be described. [Figure 12A] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 12B] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 13A] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 13B] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 13C] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 14A] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 14B] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 15A] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. [Figure 15B] 13 shows a modified example of parallelization of the manufacturing method according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.
[0029] 1 shows an example of an overall view of a can container 10 according to the present embodiment. The can container 10 according to the present invention has an EB coating layer that covers the surface, and thus can protect the can body and / or the print formed on the can body surface while improving safety for people.
[0030] The can container 10 has a reduced diameter portion 20 provided on one end side, a bottom portion 30 provided on the other end side, and a can body portion 40.
[0031] The reduced diameter portion 20 is a portion where one end of the can container 10 is reduced in diameter. The reduced diameter portion 20 may be provided at the opening of the can container 10. The reduced diameter portion 20 may be formed so that the outer diameter becomes gradually smaller as it approaches one end of the can container 10.
[0032] The reduced diameter portion 20 may be formed by performing neck processing on the end of the can container 10 before the diameter is reduced. The reduced diameter portion 20 may have a flange formed at the same time as the neck processing. A can lid can be attached by the formed flange. By providing the reduced diameter portion 20 on the can container 10, the amount of can lids used to be attached to the opening of the can container 10 can be reduced. The can container 10 may have a can lid attached.
[0033] The bottom 30 is a bottom formed at the other end of the can container 10. The bottom 30 allows the can container 10 to hold a filling such as a beverage. The bottom 30 may be formed so that the outer diameter of the bottom 30 gradually decreases toward the other end of the can container 10. The bottom surface of the bottom 30 may be formed in a dome shape that is convex upward.
[0034] The can body 40 is the region between the reduced diameter portion 20 and the bottom portion 30 of the can container 10. The can body 40 may be a cylindrical shape with a substantially constant outer diameter in the longitudinal direction (the vertical direction in FIG. 1 ) of the can container 10. The can body 40 has a larger outer peripheral surface area than the reduced diameter portion 20 and the bottom portion 30, and has a substantially constant outer diameter, making it a suitable region for printing on the surface.
[0035] The can body 40 may have a generally uniform, flat surface, or alternatively, the can body 40 may have irregularities such as embossing, or may have bent portions.
[0036] 1, the can container 10 may include three regions: a narrowed diameter portion 20, a bottom portion 30, and a can body portion 40. Alternatively, the can container 10 may not have the narrowed diameter portion 20. For example, when the can container 10 is a straight can or a cup, it may not have the narrowed diameter portion 20.
[0037] 2 shows an example of a cross section of a can container 10 in this embodiment. The can container 10 has three layers: a can body 110, a printed layer 120, and an EB coating layer 130. The can body 110 side (left side of the figure) is the inside of the can container 10, and the EB coating layer 130 side (right side of the figure) is the outside of the can container 10.
[0038] The can body 110 has a cylindrical shape and forms the structure of the can container 10. The can body 110 may be a seamless can such as a two-piece can or a welded can such as a three-piece can. The can body 110 may be a cup without a metal lid. The can body 110 may be formed of a single metal that can be used for beverage cans and food cans. For example, the can body 110 may be formed of aluminum, steel, or the like.
[0039] The printed layer 120 is an image layer expressing symbols, letters, designs and / or pictures, etc. The printed layer 120 is formed on the outer peripheral surface of the can body 110. The printed layer 120 is formed on at least one of the reduced diameter portion 20 and the can body portion 40.
[0040] The printed layer 120 may be a layer of a dried and cured ink composition. The printed layer 120 may contain a coloring material such as a pigment or a dye, a binder resin, and other solids of the ink composition. The ink composition may be, but is not limited to, a water-based ink, a solvent ink, an ultraviolet-curable ink, or an electron beam-curable ink.
[0041] Alternatively, the printed layer 120 may be a shrink film on which an ink image is printed, which further covers the outside of the can body 110. For example, the printed layer 120 may be formed by attaching an ink composition printed and cured on one or both sides of a shrink film to the can body 110.
[0042] The printed layer 120 may be a monochrome image or a color image including multiple colors. The printed layer 120 may be a mixture of monochrome and color in different regions.
[0043] Although not shown, a lubricating layer such as varnish may be provided between the can body 110 and the printed layer 120. In particular, a lubricating layer may be provided in the reduced diameter section 20. When an upper layer such as the printed layer 120 is formed after the reduction in diameter, the lubricating layer protects the can body 110 from damage during the reduction in diameter. On the other hand, when the upper layer is formed before the reduction in diameter, the upper layer can protect the can body 110, so a separate lubricating layer does not necessarily have to be provided.
[0044] The EB coating layer 130 protects the can body 110 and the printed layer 120 from physical and / or chemical damage. The EB coating layer 130 is formed on the outer peripheral surface of the can body 110. For example, the EB coating layer 130 may be formed on the printed layer 120 and / or directly on the can body 110. In this way, the printed layer 120 is formed between the can body 110 and the EB coating layer 130.
[0045] The EB coating layer 130 is provided on at least a part of the outer circumferential surface of the can container 10. For example, the EB coating layer 130 may be provided on at least the outer circumferential surface of the reduced diameter portion 20. By providing the EB coating layer 130, the can body 110 and the printed layer 120 can be protected, and color transfer from the printed layer 120 can be prevented. Furthermore, the EB coating layer 130 can make the can feel smooth to the touch.
[0046] The EB coating layer 130 contains an electron beam curable resin. Electron beam curable resin is safer for the human body than UV curable resin, etc. By providing the EB coating layer 130 on a portion that comes into contact with the human body (for example, the reduced diameter portion 20 that is likely to come into contact with the mouth), the safety of the can container 10 can be improved.
[0047] The EB coating layer 130 may be formed by reacting a reactive oligomer (e.g., an acrylic modified resin) and a reactive monomer (e.g., an acrylate monomer) with an electron beam. Details will be described later. For example, the EB coating layer 130 may include a resin formed by polymerizing an oligomer selected from polyol polyacrylate, polyester acrylate, epoxy acrylate, polyurethane acrylate, silicon acrylate, melamine acrylate, and polyether acrylate.
[0048] The thickness of the EB coating layer 130 may be 0.1 to 50 μm, preferably 0.5 to 20 μm, and more preferably 1 to 10 μm. By reducing the amount of electron beam curable resin used and ensuring that the thickness of the EB coating layer 130 satisfies the above range, the printing layer 120 and the like can be appropriately protected.
[0049] It is desirable for the EB coating layer 130 to have a certain degree of cross-linking. For example, the gel fraction of the EB coating layer 130 may be 80% or more. The gel fraction is measured in a manner similar to that of JIS K 6796, but methyl ethyl ketone (MEK) is used as the solvent instead of xylene.
[0050] The degree of crosslinking of the EB coating layer 130 may be 5 or more times at a load of 500 g as evaluated by a rubbing method. The rubbing method is performed by the following method. The detailed procedure may be in accordance with JIS K5600-8. (1) Wrap eight layers of gauze around the hemispherical tip (R7) of a cylindrical rod with a diameter of 15 mm. (2) Add 1 ml of methyl ethyl ketone (MEK) to the gauze to moisten it. (3) The moistened gauze is brought into contact with the measurement target (EB coating layer 130), a load of 500 g is applied, and the rod is then moved back and forth over a width of approximately 5 cm. (4) Measure the number of reciprocating movements until the surface of the test object peels off.
[0051] In this example, the printed layer 120 and the EB coating layer 130 are formed on both the reduced diameter portion 20 and the can body portion 40. Alternatively, at least a portion of the printed layer 120 and the EB coating layer 130 may not be formed on the reduced diameter portion 20. For example, the printed layer 120 and the EB coating layer 130 may not be formed on the reduced diameter portion 20. For example, the EB coating layer 130 may be formed on the reduced diameter portion 20, but the printed layer 120 may not be formed.
[0052] The printed layer 120 and the EB coating layer 130 may not be formed on the bottom 30. Alternatively, the printed layer 120 and the EB coating layer 130 may be formed on the bottom 30. The can container 10 may have other layers not shown. For example, an inner surface protection layer may be formed on the inside of the can body 110 (the left side of the figure).
[0053] 3 shows a modified cross section of the can container 10 in this embodiment. In this example, the can body 110 is not made of a single metal, but has a can body 112 as a core, and resin films 114 and 116 covering the inner and / or outer surfaces of the can body 112.
[0054] The can body 112 may be a metal layer usable for beverage cans and food cans, such as aluminum or steel. The resin films 114 and 116 may be polyethylene terephthalate (PET) films. For example, the can body 110 may be formed by laminating a PET film onto the inner and outer surfaces of a metal plate. The can body 110 may be a TULC (Toyo Ultimate Can) or aTULC (Aluminum Toyo Ultimate Can) manufactured by Toyo Seikan Co., Ltd.
[0055] By using can body 110 covered with a resin film in this manner, it is possible to prevent the contents from being adsorbed to can body 110. In addition, the amount of lubricant and water used during molding of can body 110 can be reduced.
[0056] The previously described configurations of the printing layer 120, the EB coating layer 130, and the like may be the same as those previously described unless otherwise specified. The same applies hereinafter.
[0057] 4 shows a modified cross section of the can container 10 in this embodiment. In this example, the can container 10 further has a UV coating layer 140. The UV coating layer 140 is formed on the outer peripheral surface of the can body 110.
[0058] For example, the UV coating layer 140 may be provided entirely between the printed layer 120 and the EB coating layer 130. For example, the UV coating layer 140 may be provided partially between the printed layer 120 and the EB coating layer 130. In this case, at least a portion of the printed layer 120 is provided between the can body 110 and the UV coating layer 140.
[0059] When the surface of the can body 110 includes an area where the printed layer 120 is not formed, the UV coating layer 140 may be formed directly on the outer circumferential surface of the can body 110. In this case, at least a portion of the UV coating layer 140 may be provided between the can body 110 and the EB coating layer 130.
[0060] In this way, the UV coating layer 140 covers and protects the can body 110 and / or the printed layer 120. Furthermore, at least a portion of the UV coating layer 140 is coated with the EB coating layer 130. As a result, the surface of the can container 10 is further protected by the UV coating layer 140 in addition to the EB coating layer 130, while providing the EB coating layer 130 on at least a portion of the outer circumferential surface increases safety for people.
[0061] The UV coating layer 140 contains an ultraviolet curing resin. The UV coating layer 140 may be a cured ultraviolet curing resin composition such as a photocationic polymerizable resin composition or a photoradical polymerizable composition.
[0062] In this example, the printed layer 120, the EB coating layer 130, and the UV coating layer 140 are formed on both the reduced diameter portion 20 and the can body 40. Alternatively, at least a portion of the printed layer 120, the EB coating layer 130, and the UV coating layer 140 may not be formed on the reduced diameter portion 20.
[0063] For example, the printing layer 120, the EB coating layer 130, and the UV coating layer 140 may not be formed in the reduced diameter section 20. For example, only the EB coating layer 130 may be formed in the reduced diameter section 20, and the printing layer 120 and the UV coating layer 140 may not be formed. For example, the EB coating layer 130 and the UV coating layer 140 may be formed in the reduced diameter section 20, and the printing layer 120 may not be formed.
[0064] 5 shows a modified cross section of the can container 10 in this embodiment. The EB coating layer 130 may be formed only on a part of the outer circumferential surface of the can body 110. For example, the EB coating layer 130 may be provided only on the narrowed diameter portion 20. This makes it possible to reliably coat the portion where safety is highly required (for example, the narrowed diameter portion 20) with the EB coating layer 130 while reducing the amount of electron beam curable resin used.
[0065] In this embodiment, the UV coating layer 140 may be provided on the entire or part of the outer circumferential surface of the can body 110. When the surface of the can body 110 includes an area where the printed layer 120 is not formed, the UV coating layer 140 may be formed directly on the outer circumferential surface of the can body 110. In this case, at least a portion of the UV coating layer 140 may be provided between the can body 110 and the EB coating layer 130.
[0066] 6 shows a modified cross section of the can container 10 in this embodiment. The EB coating layer 130 may be formed only on a portion of the outer circumferential surface of the can body 110. The UV coating layer 140 may be formed only on a portion of the outer circumferential surface of the can body 110. For example, the UV coating layer 140 may be formed on a portion where the EB coating layer 130 is not provided. As an example, the EB coating layer 130 may be formed on the reduced diameter portion 20, and the UV coating layer 140 may be formed on the can body portion 40.
[0067] This allows the portions requiring high safety (for example, the reduced diameter portion 20) to be reliably covered with the EB coating layer 130, while other portions are protected with the UV coating layer 140. Note that, although the UV coating layer 140 and the EB coating layer 130 are formed so as not to overlap each other in Fig. 6, there may be an overlap between the two layers at the boundary portion or the like.
[0068] 7 shows a modified cross section of the can container 10 in this embodiment. The EB coating layer 130 may be formed on the outer peripheral surface of the can body 110 in a predetermined geometric pattern. For example, the EB coating layer 130 may be formed on the outer peripheral surface of the can body 110 in a stripe pattern along the horizontal direction (horizontal direction in the figure) of the can body 110. This makes it possible to reduce the amount of electron beam curable resin used while protecting the surface of the can container 10 with the highly safe EB coating layer 130. The UV coating layer 140 may be at least partially omitted.
[0069] 7, the EB coating layer 130 may be formed on the outer peripheral surface of the can body 110 in a stripe pattern along the vertical direction of the can body 110 (the longitudinal direction in the figure). Alternatively, the EB coating layer 130 may be formed on the outer peripheral surface of the can body 110 in a stripe pattern along a diagonal direction of the can body 110. The EB coating layer 130 may be formed on the outer peripheral surface of the can body 110 in a pattern in which a plurality of stripes in different directions are mixed.
[0070] 2 to 7 illustrate an example of the form of the can container 10, but the present invention is not limited thereto. For example, in Fig. 2 to Fig. 7, the can container 10 may not include the printed layer 120. For example, the can container 10 may be a white can or a plain can for which the printed layer 120 is to be formed later on the can body 40 or the like, in which case the can container 10 does not include the printed layer 120.
[0071] Also, two or more of the configurations described in Figures 2 to 7 may be combined. For example, can body 110 having can body 112 in Figure 3 and resin films 114 and 116 covering the inner and / or outer surface of can body 112 may be applied to the configurations shown in Figures 4 to 7.
[0072] 8A and 8B show an example of a flow of a manufacturing method of the can container 10 in this embodiment. The can container 10 in this embodiment can be manufactured by the processes of S100 to S800 in Fig. 8A. For convenience of explanation, the processes of S100 to S800 will be explained in order, but each process may be interchanged and / or some of the processes may be omitted without departing from the spirit of the present invention.
[0073] First, in S100, molding is performed to form the bottom 30 and the can body 40 of the can container 10. There are two types of molding: wet molding, which uses water, and dry molding, which does not use water.
[0074] Fig. 9 shows an example of a subflow (wet molding) of S100 in Fig. 8A. S100 (wet molding) may be performed by executing S105 to S170 in Fig. 9.
[0075] In S105, the coiled metal plate is uncoiled and stretched (uncoiled). The plate may be an aluminum plate or a steel plate, but is not limited thereto.
[0076] In S110, a process (lubricator) is performed in which a lubricant is applied to the stretched plate material. The lubricant may be a known one.
[0077] In S120, a process (cupping press) is performed to punch out the plate material to which the lubricant has been applied into a cup shape.
[0078] In S130, the cup-shaped member is subjected to drawing and ironing processes to thin and stretch the sides of the cup. Furthermore, a dome-shaped bottom is formed at the same time, thereby forming the can body 40 and the bottom 30 (body maker). A cooling / lubricant (coolant) may be used separately during processing.
[0079] In S140, a process (trimmer) is performed to remove unnecessary portions of the molded member.
[0080] In S150, the molded parts are washed and dried, and a process (washer) is performed to remove the lubricant.
[0081] In S155, a lubricating layer is formed by applying varnish or the like to the outer circumferential surface of the washed member (i.e., the outer surface of the cup), which makes it possible to prevent the surface of the can body 110 from being scratched in the diameter reduction step described later.
[0082] In S170, an inner surface protective layer is formed on the inner circumferential surface of the member after cleaning (i.e., the inner surface of the cup). For example, the inner surface protective layer may be formed by applying paint to the inner circumferential surface and baking it. This makes it possible to prevent the inner circumferential surface from being scratched.
[0083] Fig. 10 shows an example of a subflow (dry molding) of S100 in Fig. 8A. S100 (dry molding) may be performed by executing S105 to S140 in Fig. 9.
[0084] The process of S105 (uncoiler) may be the same as that of S105 in FIG.
[0085] In S115, a resin film is laminated on one or both sides of the plate material by a known method, for example, the method described in JP-A-2004-25640.
[0086] The resin film may be a thermoplastic resin such as polyethylene terephthalate (PET). Instead of the thermoplastic resin, a thermosetting resin such as a thermosetting acrylic resin, a thermosetting epoxy resin, a thermosetting polyurethane resin, or a thermosetting polyester resin may be used. By using the resin film, molding can be realized without using the lubricant used in S110, S120, and S130 in Fig. 9, so the cleaning step of S150 can be omitted.
[0087] The thickness of the resin film may be 0.5 μm or more and 30 μm or less. If the thickness of the resin film is less than 0.5 μm, the surface of the resin film becomes less slippery, and there is a risk that the can body 110 may be scratched or metal powder may adhere to the tool when forming the reduced diameter portion 20. If the thickness of the resin film exceeds 30 μm, there is a risk that the resin adhesion after the reduction processing and the flange processing may be poor.
[0088] Before laminating the resin film, a primer composition may be applied to the lamination surface of the plate. For example, a primer composition containing a polyester resin, a curing agent and / or a solvent may be roll-coated on the plate, baked to form a primer layer, and then a resin film may be laminated on the primer layer. The curing agent may be, for example, a resol-type phenolic resin derived from m-cresol.
[0089] The primer composition may further contain a coloring material such as a pigment and / or a food coloring, etc. This can enhance the decorativeness even in a portion of the can container 10 where the printed layer 120 is not provided (e.g., the bottom portion 30, etc.).
[0090] The processes of S120 to S140 may be the same as those described in Fig. 9. Here, a heat treatment (not shown) may be performed between S130 and S140 or after S140. By performing the heat treatment, distortion of the resin film that occurs during molding can be removed.
[0091] In dry molding, the processes after S150 can be omitted. On the other hand, in dry molding, S155 may be performed to form a lubricant layer on the resin film. In particular, in dry molding, the lubricant layer may be formed with a highly volatile lubricant. Even if a highly volatile lubricant is used, a part of the lubricant layer remains on the resin film. For example, hexane may be used as the lubricant. After the process of S100, the process of S200 is performed.
[0092] In S200, the formed can body 110 is necked to form the reduced diameter portion 20. The necking may be performed using a known die-necking tool. Simultaneously with or after the necking, the can body 110 may be flanged to form a flange for attaching a can lid.
[0093] After necking, a treatment for removing the lubricating layer may be performed. For example, at least a part of the lubricating layer may be removed by washing with water or heating. Heating may be performed using a hot air heating device, an induction heating (IH) device, and / or an infrared (IR) heating device. In particular, when forming a printing layer in S300 after S200, it is preferable to remove the lubricating layer to prevent ink repellency.
[0094] In S300, a printing step is performed to form a printed layer 120 on the outer peripheral surface of the cylindrical can body 110. The printed layer 120 may be formed on the can body 110 by performing inkjet printing and / or plate printing.
[0095] Inkjet printing may be a method in which an ink composition is ejected directly onto the can body 110 from an inkjet head (IJH) of an inkjet printing device, or an offset method in which an ink composition ejected from the IJH onto a blanket (i.e., a transfer plate) is transferred to the can body 110.
[0096] Plate printing may be a method of transferring the ink composition to the can body 110 using a plate such as a relief printing plate. The ink composition may be directly transferred to the can body 110 using a relief printing plate, or an offset method may be used in which the ink composition transferred to a blanket (i.e., a transfer plate) is further transferred to the can body 110.
[0097] The ink composition may be a water-based ink, a solvent ink, an ultraviolet-curable ink, or an electron beam-curable ink. The ink composition may contain a colorant selected from pigments and dyes, a resin binder, a monomer / oligomer, an initiator, a solvent, and / or additives such as a dispersant, as necessary.
[0098] After printing, the ink composition may be dried and cured by, for example, air drying, heat treatment, ultraviolet irradiation, electron beam irradiation, or a combination of these, depending on the type of ink composition.
[0099] The printed layer 120 may be formed on the entire or partial area of the outer peripheral surface of the can body 110. For example, the printed layer 120 may be formed on the entire or only a portion of the can body 40. For example, the printed layer 120 may be formed on the entire or only a portion of the reduced diameter portion 20 and the entire or only a portion of the can body 40.
[0100] The printing layer 120 may be formed in parallel. For example, the process of S300 may be performed simultaneously by a plurality of inkjet printing devices and / or a plurality of plate-based printing devices. This will be described in detail later.
[0101] The printed layer 120 may be formed in multiple batches. For example, a common design, common pattern, and / or common characters may be formed in advance by plate printing or inkjet printing, and then individual designs, individual patterns, and / or individual characters that differ for each product or lot may be formed on demand later by inkjet printing. When the printed layer 120 is not formed, such as when manufacturing blank cans or plain cans to be later printed, the process of S300 may be omitted.
[0102] In S400, a UV coating layer 140 is formed on the can body 110 after the diameter reduction. For example, the UV coating layer 140 may be formed by a UV coating step of coating an ultraviolet curable resin composition on the outer peripheral surface of the cylindrical can body 110, and a UV curing step of irradiating the ultraviolet curable resin composition with ultraviolet light to cure it, thereby forming a UV coating layer containing an ultraviolet curable resin on the outer peripheral surface of the can body 110. If necessary, for example, when the ultraviolet curable resin composition contains a solvent, a drying step may be provided between the UV coating step and the UV curing step.
[0103] When the printed layer 120 is formed, an ultraviolet curable resin composition may be formed on the printed layer 120 in a UV coating step. As a result, a UV coating layer 140 may be formed on the entire surface of the printed layer 120 or on a part of the printed layer 120, as shown in Fig. 4, for example. The UV coating layer 140 may also be formed on the can body 110 on which the printed layer 120 is not formed. The UV coating layer 140 may be provided in a stripe shape by a stripe coater.
[0104] The UV coating layer 140 may be formed on the entire or partial area of the outer circumferential surface of the can body 110. For example, the UV coating layer 140 may be formed on only the entire or partial can body portion 40. For example, the UV coating layer 140 may be formed on only the entire or partial reduced diameter portion 20 and the entire or partial can body portion 40.
[0105] The ultraviolet curing resin composition may be a transparent or nearly transparent resin composition containing an ultraviolet curing resin and an initiator. The ultraviolet curing resin may be a photocationic polymerizable resin or a photoradical polymerizable resin. The initiator may be a photocationic initiator or a photoradical initiator depending on the type of ultraviolet curing resin. The ultraviolet curing resin composition may further contain additives such as a solvent, a sensitizer, a catalyst and / or a pigment as necessary.
[0106] The UV coating step may be performed by a coating device such as a roll coater, etc. Additionally / alternatively, the UV coating step may be performed by a printing device such as a plate printing device and / or an inkjet printing device.
[0107] In the UV coating step, the ultraviolet curable resin composition may be coated to a predetermined thickness. For example, the thickness of the ultraviolet curable resin composition in the UV coating step may be 0.1 to 50 μm, preferably 0.5 to 20 μm, and more preferably 1 to 10 μm. The UV curing step may be performed by irradiating the ultraviolet curable resin composition after coating or drying with an electron beam of a predetermined intensity using an ultraviolet irradiation device.
[0108] The formation of the UV coating layer 140 may be performed in parallel. For example, the UV coating process may be parallelized by applying the ultraviolet curing resin composition in parallel using a plurality of UV coating devices. The UV curing process may be parallelized using a plurality of ultraviolet irradiation devices. If the UV coating layer 140 is not formed, the process of S400 may be omitted.
[0109] In S500, the EB coating layer 130 is formed on the can body 110 after the diameter reduction. For example, the EB coating layer 130 may be formed by an EB coating step of coating an electron beam curable resin composition on the outer peripheral surface of the cylindrical can body 110, and an EB curing step of irradiating the electron beam curable resin composition with an electron beam to cure it, thereby forming an EB coating layer containing the electron beam curable resin on the outer peripheral surface of the can body 110. If necessary, for example, when the electron beam curable resin composition contains a solvent, a drying step may be provided between the EB coating step and the EB curing step.
[0110] When the printed layer 120 is formed, the EB coating step may be performed by forming an electron beam curable resin composition on the printed layer 120. For example, as shown in FIG. 2, an EB coating layer 130 may be formed on the entire surface of the printed layer 120 or on a part of the printed layer 120.
[0111] When the UV coating layer 140 is formed, the EB coating step may be performed by forming an electron beam curable resin composition on the UV coating layer 140. For example, the EB coating layer 130 may be formed on the entire surface of the UV coating layer 140 or on a part of the UV coating layer 140 as shown in FIG.
[0112] The EB coating step may be performed by forming the electron beam curable resin composition on the can body 110 on which the printing layer 120 and the UV coating layer 140 are not formed. The EB coating layer 130 may be provided in a stripe pattern by a stripe coater as shown in FIG.
[0113] The EB coating layer 130 may be formed on the entire or partial area of the outer peripheral surface of the can body 110. For example, the EB coating layer 130 may be formed on the entire or only part of the narrowed portion 20. For example, the EB coating layer 130 may be formed on the entire or only part of the can body 40. For example, the EB coating layer 130 may be formed on the entire or part of the narrowed portion 20 and the entire or part of the can body 40.
[0114] The electron beam curable resin composition may be an electron beam curable resin itself or a transparent or nearly transparent resin composition containing an electron beam curable resin. The electron beam curable resin may contain a reactive oligomer, a reactive monomer, and / or other additives that are highly reactive to electron beams. The electron beam curable resin composition does not require an initiator that is a concern for human safety, and is therefore safer than an ultraviolet ray curable resin composition.
[0115] The reactive oligomer may be an acrylic modified resin containing (meth)acrylic groups selected from polyol polyacrylates, polyester acrylates, epoxy acrylates, polyurethane acrylates, silicone acrylates, melamine acrylates, polyether acrylates, and the like.
[0116] The reactive monomer may be a monofunctional or polyfunctional acrylate selected from acrylic acid, ethyl acrylate, butyl acrylate, N-vinylpyrrolidone, hexadiol acrylate, tripropylene glycol diacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, trimethylolpropane triacrylate, glycerol propoxy triacrylate, trimethylolpropanethoxy triacrylate, and pentaerythritol triacrylate.
[0117] The additives used may be selected from fillers, binder resins, pigments, leveling agents, solvents, antifoaming agents, and the like, as required.
[0118] The EB coating step may be performed by a coating device such as a roll coater. Additionally / alternatively, the EB coating step may be performed by a printing device such as a plate printing device and / or an inkjet printing device.
[0119] In the EB coating step, the electron beam curable resin composition may be coated to a predetermined thickness. For example, the thickness of the electron beam curable resin composition coated in the EB coating step may be 0.1 to 50 μm, preferably 0.5 to 20 μm, and more preferably 1 to 10 μm.
[0120] The EB curing step is carried out by irradiating the applied or dried electron beam curable resin composition with an electron beam of a predetermined intensity using an electron beam irradiation device. For example, the intensity of the electron beam in the EB curing step may be 2 to 100 kGy.
[0121] The formation of the EB coating layer 130 may be performed in parallel. For example, the EB coating process may be parallelized by applying the electron beam curable resin composition in parallel using multiple EB coating devices. The EB curing process may be parallelized using multiple electron beam irradiation devices.
[0122] In S600, the can container 10 on which each layer has been formed is inspected. The outer or inner surface of the can container 10 may be inspected for dents, holes, and / or scratches. The printed image of the printed layer 120 may be inspected for chips, misalignments, and / or unclear areas.
[0123] In S700, the contents are filled into the can container 10. For example, the can container 10 may be filled with beverages, food, medicines, chemical products, gases, liquids and / or solids, etc.
[0124] In S800, a can lid is attached to the can container 10. For example, the can lid may be attached by placing the lid on the flange portion of the can container 10 and tightening it with a lid tightening machine.
[0125] 8 to 10 show the basic process flow for manufacturing the can container 10, but as described later, the order of the processes may be changed or parallelized. This can improve the efficiency of the can manufacturing process. Also, if the can container 10 is a cup, S700 to S800 etc. may be omitted.
[0126] As shown in Fig. 8B, the diameter reduction (necking) in S200 in Fig. 8A may be performed between the formation of the EB coating layer 130 in S500 and the inspection of the can container in S600. In this case, the can body is protected during necking by the EB coating layer 130. In this case, the process of S155 in Fig. 9 may be omitted.
[0127] S100 to S800 may be performed by a single entity / location, or by multiple different entities / locations. For example, S100 to S600 may be performed at a can factory, and S700 and onward may be performed at a filling factory (also called a packer or bottler).
[0128] Also, for example, S100 to S200 may be performed in a can manufacturing factory, and S300 and subsequent steps may be performed in a filling factory (also called a packer or bottler). This allows a printing device to be installed in the filling factory, and the can containers 110 with any image can be quickly manufactured and shipped in the number required for filling.
[0129] Fig. 11A shows an example of parallelization of the manufacturing method in this embodiment. In this example, the inkjet printing step of forming inkjet printed layers may be performed in parallel using multiple inkjet printing devices. For example, in S300, printing may be performed in parallel on the can body 110 after diameter reduction in S200 using multiple inkjet printing devices (three in the example of Fig. 11A). In addition to / instead of the multiple inkjet printing devices, multiple plate-based printing devices may be used.
[0130] The formation of the EB coating layer 130 in S500 may be performed in parallel. For example, in S500, the electron beam curable resin may be formed in parallel on the printed layer 120 of the can body 110 after printing in S300 using multiple coating devices (three in the example of FIG. 11A). Drying and / or electron beam irradiation may also be performed in parallel, or the drying and / or electron beam irradiation processes may be performed in a common device. After S500, the processes from S600 onwards may be performed.
[0131] 11B shows an example of parallelization of the manufacturing method in this embodiment. In FIG. 11B, the diameter reduction of S200 is performed after the formation of the EB coating layer 130 of S500, which may be parallelized, rather than after the molding of S100. In other respects, the same configuration as in FIG. 11A may be adopted.
[0132] 12A shows a modified example of parallelization of the manufacturing method in this embodiment. In this example, in addition to S300 and S500, the formation of the UV coating layer in S400 may also be performed in parallel. For example, in S400, a UV curable resin may be applied in parallel to the can body 110 after printing in S300 using multiple application devices (three in the example of FIG. 12A). Drying and / or ultraviolet irradiation may also be performed in parallel, or the drying and / or electron beam irradiation processes may be performed in a common device.
[0133] In S300, a plurality of plate-based printing devices may be used in addition to or instead of the plurality of inkjet printing devices. After S500, the processes from S600 onward may be executed. Points other than S400 may be the same as those in the embodiment of FIG. 11A.
[0134] Fig. 12B shows an example of parallelization of the manufacturing method in this embodiment. In Fig. 12B, the diameter reduction of S200 is performed after the formation of the EB coating layer 130 of S500, which may be parallelized, rather than after the molding of S100. In other respects, the same configuration as in Fig. 12A may be adopted.
[0135] 13A shows a modified example of the parallelization of the manufacturing method in this embodiment. In this example, the printing layer 120 is formed by combining inkjet printing and plate printing. In this example, the can body supplying step S190 may be performed after the molding step S100.
[0136] In S190, a can body supplying process is performed. In the can body supplying process, multiple cylindrical can bodies 110 are supplied to both the inkjet printing process and the plate printing process in which a plate-printed layer is formed on the outer peripheral surface of the cylindrical can body by plate printing, in response to a request from a downstream process. For example, the number of can bodies to be subjected to inkjet printing is supplied to the inkjet printing device, and the number of can bodies to be subjected to plate printing is supplied to the plate printing.
[0137] Before the can body supplying step, a storage step may be performed in which a plurality of cylindrical can bodies 110 that have been formed (S100) are stored. This allows the formed can bodies 110 to be stored for the subsequent can body supplying step until they are needed.
[0138] The can body 110 supplied for inkjet printing is subjected to diameter reduction in S200A. The diameter reduction in S200A may be performed in the same manner as in S200.
[0139] After S200A, in S300A, inkjet printing is performed on the reduced can body 110. S300A may be performed in the same manner as the inkjet printing in S300. The printing in S300A may or may not be performed in parallel.
[0140] After S300A, in S500, the EB coating layer 130 is formed on the printed can body 110. The process of S500 may or may not be performed in parallel. After S500, the processes from S600 onwards may be performed.
[0141] In S300B, the can bodies 110 supplied for plate printing are subjected to plate printing. S300B may be performed in the same manner as the plate printing in S300.
[0142] After S300B, a lubricating layer such as varnish is formed in S350. For example, the lubricating layer may be formed by applying varnish and then baking it. Since the printed layer 120 is provided in S300B on the lubricating layer formed in S155 and the resin film laminated in S115, S350 is performed if a lubricating layer is to be provided again on the surface. The process of S350 may be omitted.
[0143] After S350, diameter reduction is performed in S200B. The diameter reduction in S200B may be performed in the same manner as S200. After S200B, processing from S400 or S500 onwards may be performed. Processing from S200A onwards may be the same as that in FIG. 11A. A UV coating layer may be formed in the same manner as in FIG. 12A. According to the embodiment in FIG. 13A, the molded can body 110 can be printed by various printing methods such as inkjet printing and plate printing. Note that, although an example in which S300A and S500 are parallelized has been described in FIG. 13A, S300A and / or S500 do not have to be parallelized.
[0144] FIG. 13B shows an example of parallelization of the manufacturing method in this embodiment. In FIG. 13B, instead of forming a lubricating layer such as varnish in S350 after plate printing in S300B in the embodiment of FIG. 13A, and then shrinking in S200B and forming the EB coating layer 130 in S500, the EB coating layer 130 may be formed after plate printing in S300B, and then shrinking in S200B. As a result, the EB coating layer 130 also functions as a lubricating layer, so the formation of the lubricating layer in S350 can be omitted. In other respects, the same configuration as in FIG. 13A may be adopted.
[0145] Figure 13C shows an example of parallelization of the manufacturing method in this embodiment. In Figure 13C, unlike the embodiment of Figure 13A, the diameter reduction in S200 may be performed after the formation of the EB coating layer 130 in S500. In this case, the EB coating layer 130 also functions as a lubricating layer for diameter reduction. In other respects, the same configuration as in Figure 13A may be adopted.
[0146] FIG. 14A shows a modified example of the parallelization of the manufacturing method in this embodiment. In this example, in the diameter reduction step S200, a common diameter reduction device is used to reduce the diameter of a part of the can body 110 before it is supplied to the inkjet printing step and the can body 110 that has been through the plate printing step to form a reduced diameter portion. For example, the diameter reduction equipment such as a die necking tool in S200A in FIG. 13 and the diameter reduction equipment in S200B are shared to perform the S200 (diameter reduction) process. This makes it possible to save the equipment, resources, and costs required for manufacturing the can container 10. The process after S200 may be the same as that in FIG. 11A. A UV coating layer may be formed before S500 in the same manner as in FIG. 12A. Note that, although an example in which S300A and S500 are parallelized is described in FIG. 14A, S300A and / or S500 do not need to be parallelized.
[0147] Fig. 14B shows an example of parallelization of the manufacturing method in this embodiment. In Fig. 14B, unlike the embodiment in Fig. 14A, the formation of the EB coating layer 130 in S500 may be performed first instead of the formation of the lubricating layer such as varnish in S350. In this case, the EB coating layer 130 also functions as a lubricating layer for diameter reduction. In other respects, the same configuration as in Fig. 14A may be adopted.
[0148] 15A shows a modified example of the parallel manufacturing method of this embodiment, in which both plate printing and inkjet printing are performed on a molded can body 110.
[0149] First, in S190, a process is performed in which the molded can bodies 110 are divided into those to be printed only by inkjet printing and those to be printed in combination with plate printing and inkjet printing according to the request. The number of can bodies to be printed only by inkjet printing is supplied to the diameter reduction process in S200, and then inkjet printing is performed in S300A. The can bodies 110 to be printed only by inkjet printing in this way are processed in the same manner as in the example of FIG. 11A.
[0150] Meanwhile, the number of can bodies to be used together is supplied to a plate printing process (S300B). The plate printing (S300B) is performed before the inkjet printing process (S300A). A plate printing layer is formed on the outer peripheral surface of the cylindrical can body 110 by the plate printing (S300B). The plate printing layer can express a common design, a common pattern, and / or common characters, etc. Thereafter, a lubricating layer such as varnish is formed in S350, and the can bodies are then supplied to a diameter reduction process in S200.
[0151] After the diameter reduction, inkjet printing of S300A is performed to form an inkjet printing layer. The inkjet printing layer can express a common design, a common pattern, and / or common characters, etc. The can body 110 after the diameter reduction may be stored in a warehouse or the like until there is a request for inkjet printing.
[0152] 15A, common designs and the like that are produced in large quantities can be printed on the can bodies 110 by plate printing, while individual designs and the like can be printed on demand by inkjet printing. S200 and thereafter may be the same as in FIG. 11A. Before S500, a UV coating layer may be formed in the same manner as in FIG. 12A. Note that, although an example in which S300A and S500 are parallelized has been described in FIG. 15A, S300A and / or S500 do not need to be parallelized.
[0153] FIG. 15B shows an example of parallelization of the manufacturing method in this embodiment. In FIG. 15B, unlike the embodiment of FIG. 15A, the EB coating layer 130 may be formed in S500 instead of the lubricating layer such as varnish in S350. In this case, the EB coating layer 130 also functions as a lubricating layer for diameter reduction. In this case, after the plate printing in S300B and the formation of the EB coating layer in S500, the diameter reduction in S200 and the inkjet printing in S300A may be performed, and the EB coating layer in S500 may be formed again. Alternatively, the formation of the EB coating layer for the second time may be omitted. In other respects, the same configuration as in FIG. 15A may be adopted.
[0154] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.
[0155] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the can body, can container, and method shown in the claims, specification, and drawings is not specifically indicated as "before," "prior to," etc., and can be realized in any order, as long as the can body or can container from the previous process is not used in the subsequent process. Even if the operational flow in the claims, specification, and drawings is described using "first," "next," etc. for convenience, it does not mean that it is essential to perform the process in this order. [Explanation of symbols]
[0156] 10 Can containers 20 Reduced diameter part 30 bottom 40 Can body 110 Can body 112 Can body 114 Resin film 116 Resin Film 120 printing layer 130 EB coating layer 140 UV coating layer
Claims
1. A cylindrical can body; an EB coating layer formed on an outer peripheral surface of the can body and including an electron beam curable resin; A can container comprising:
2. The EB coating layer is formed only on a part of the outer circumferential surface of the can body. The can container according to claim 1.
3. the EB coating layer is formed on the outer peripheral surface of the can body in a stripe-shaped pattern extending along the horizontal direction of the can body; The can container according to claim 1.
4. The can body has a reduced diameter portion whose one end is reduced in diameter and a can body portion, The EB coating layer is provided on at least an outer peripheral surface of the reduced diameter portion. The can container according to claim 1.
5. The thickness of the EB coating layer is 0.5 to 20 μm. The can container according to claim 1.
6. The EB coating layer contains a resin in which an oligomer selected from polyol polyacrylate, polyester acrylate, epoxy acrylate, polyurethane acrylate, silicon acrylate, melamine acrylate, and polyether acrylate is polymerized. The can container according to claim 1.
7. Further comprising a printing layer between the can body and the EB coating layer. A can container according to any one of claims 1 to 6.
8. The can body has a can body and a resin film covering the inner surface and / or the outer surface of the can body. A can container according to any one of claims 1 to 6.
9. The can further includes a UV coating layer formed on an outer peripheral surface of the can body and containing an ultraviolet curing resin. The can container according to claim 1.
10. The UV coating layer is at least partially disposed between the can body and the EB coating layer. The can container according to claim 9.
11. A printing layer is further provided between the can body and the EB coating layer, The printing layer is at least partially provided between the can body and the UV coating layer. The can container according to claim 10.
12. an EB coating step of coating an electron beam curable resin composition on an outer peripheral surface of a cylindrical can body; an EB curing step of irradiating the electron beam curable resin composition with an electron beam to cure it, thereby forming an EB coating layer containing an electron beam curable resin on the outer peripheral surface of the can body; A method for manufacturing a can container comprising the steps of:
13. a printing step of forming a printing layer on an outer peripheral surface of a cylindrical can body, which is performed before the EB coating step; The EB coating step is carried out by forming the electron beam curable resin composition on the printing layer. A method for producing the can container according to claim 12.
14. The intensity of the electron beam in the EB curing step is 2 to 100 kGy. A method for producing the can container according to claim 12.
15. The thickness of the electron beam curable resin composition applied in the EB application step is 0.5 to 20 μm. A method for producing the can container according to claim 12.
16. an EB coating step of coating an electron beam curable resin composition on outer peripheral surfaces of a plurality of cylindrical can bodies in parallel using a plurality of EB coaters; an EB curing step of irradiating the electron beam curable resin composition with an electron beam to cure it, thereby forming an EB coating layer containing an electron beam curable resin on the outer peripheral surface of the can body; A method for manufacturing a can container comprising the steps of:
17. an inkjet printing step, which is performed before the EB coating step, of forming inkjet printed layers in parallel on an outer peripheral surface of a cylindrical can body by a plurality of inkjet printing devices; The EB coating step is performed by forming the electron beam curable resin composition on the inkjet printing layer. A method for producing the can container according to claim 16.
18. a can body supplying process for supplying a plurality of the cylindrical can bodies to both the inkjet printing process and a plate printing process for forming a plate printing layer on an outer peripheral surface of the cylindrical can body by plate printing; The method for manufacturing a can container according to claim 17, comprising:
19. a diameter reducing step of reducing a part of the can body using a common diameter reducing device to form a reduced diameter portion on the can body before being supplied to the inkjet printing step and the can body that has been subjected to the plate printing step; The method for manufacturing a can container according to claim 18, comprising:
20. a plate printing step, which is carried out before the inkjet printing step, for forming a plate-printed layer on the outer peripheral surface of the cylindrical can body by plate printing; The method for manufacturing a can container according to claim 17, comprising:
21. a storage step of storing the plurality of cylindrical can bodies before the can body supply step; The method for manufacturing a can container according to claim 18, comprising:
22. The EB coating device is an inkjet printing device. A method for producing the can container according to claim 16.