JPH0929842A - Metal can body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the damage of the end of a synthetic resin film even by posttreating such as necking by so sticking the upper end of the film to a can body as to expose the opening end of the body, and covering the upper ends of the body, opening end of the resin film with a protective film. SOLUTION: A print layer 16 is formed on a synthetic resin film 14 by gravure printing, and an adhesive layer 17 is formed on the layer 16. The film 14 formed with the layer 16 is stuck in the state having an interval L to the end face 12C of the opening end 12B of a can body 12 by the layer 17. The interval L is set to the size to be concealed when a can cover is laminated and rolled on the opening end 12B of the two-piece body 10. Then, a protective film 20 is formed on the surface of the opposite side to the surface of the film 14 formed with the layer 16. The film 20 is formed on only the upper part 14A of the film 14 from the end face 12C of the opening end 12B of the body 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal can body used for aerosol cans, beverage cans, and the like, and more specifically, printing even after post-processing such as necking, flanging and curling. The present invention relates to a metal can body in which an end portion of an already-made synthetic resin film is not damaged.

[0002]

2. Description of the Related Art For metal can bodies, especially for two-piece cans made of aluminum or the like, it has been required to perform high-grade printing on the cans. Conventionally, in order to perform high-grade printing, it is known to adhere a high-quality printed sheet-like film to the outer peripheral surface of a two-piece can.
It is proposed by Japanese Patent Laid-Open No. 57747. The can body to which the film is adhered is subjected to post-treatments such as a necking process, flanging, or curling.

[0003]

However, at the time of post-processing such as the above-mentioned necking processing, the end of the film is damaged because the end of the film on the opening side of the can body receives a processing load. However, there is a problem such as peeling between the film and the can body. In addition, when cleaning metal cans, retort sterilization, pasteurizer sterilization, or temperature inspection with hot water in aerosol cans, water and hot water intrude between the edge of the film and the metal can, causing film peeling and metal corrosion. And deteriorate the appearance. Further, when the can body is made of aluminum, the metal of the can body adheres to the tool during the necking process or the like, which prevents continuous production.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a metal can body used for an aerosol can, a beverage can, or the like in which the end portion of the synthetic resin film is not damaged even after post-processing such as necking. To provide.

[0005]

The present invention has been proposed in order to achieve the above object, and is characterized by the following points. That is, according to the present invention, a synthetic resin film having a printing layer and an adhesive layer formed on one surface thereof is located at a position where the upper end of the synthetic resin film exposes the open end of the can body. In this state, the metal can body is adhered to the can body through the adhesive, and at least the opening end of the can body and the upper end of the synthetic resin film are covered with a protective coating. .

Further, according to the present invention, there is provided the metal can body according to claim 1, wherein the opening from the can end to the upper end of the synthetic resin film is covered with a protective coating. To be done.

Further, according to the present invention, the metal can body according to claim 1, wherein the can end is covered with a protective film from the opening end to the synthetic resin film of the portion to be post-processed. A can body is provided.

Further, according to the present invention, there is provided a metal can body in which a synthetic resin film is coated with a protective coating on the upper end portion, the lower end portion and both end portions in the circumferential direction.

Further, according to the present invention, a synthetic resin film having a printed layer formed on one surface and an adhesive layer formed on the other surface is provided, and the upper end of the synthetic resin film is the can body. Adhesive to the can body in a state where the open end is located at the exposed position, and the entire upper end, lower end, and both ends in the circumferential direction of the synthetic resin film and the printing layer were covered with a protective coating. A featured metal can body is provided.

Further, according to the present invention, claims 1 to 5 are provided.
A metal can body in which the opening end of the aluminum can body including the end face and the upper end of the synthetic resin film are covered with a protective coating.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the metal can body according to the invention of claim 1, a synthetic resin film having a printing layer and an adhesive layer formed on one surface thereof is provided with an adhesive, and the upper end of the film is the can. It is bonded to a position where the open end of the barrel is exposed, and at least the open end of the can barrel and the upper end of the synthetic resin film are covered with a protective coating. Therefore, when performing a necking process which is a post-process, the upper end of the synthetic resin film is covered with the protective film from the opening end of the can body, and thus the upper end of the synthetic resin film is damaged. Is prevented, and the upper end of the synthetic resin film does not peel off from the can body.

[0012] In the metal can body according to the invention of claim 2, in the metal can body of claim 1, from the opening end of the can body to the upper end of the synthetic resin film is covered with a protective coating. In addition, it is not necessary to use a large amount of paint forming a protective film and it is not necessary to heat the entire can body when the paint is cured.

In the two-piece metal can body according to the third aspect of the invention, in the metal can of the first aspect, only the synthetic resin film in the portion to be post-processed from the opening end of the can body is protected by the protective coating. Since it is covered, it has the same effect as in claim 3 above.

In the metal can body according to the invention of claim 4, in the metal can body of the above claim 1, the synthetic resin film, including the upper end portion, the lower end portion and both circumferential end portions, is entirely protected by a protective film. Since it is covered, water or warm water does not enter between the synthetic resin film and the can body, and neither peeling of the film nor corrosion of the metal occurs.

In a metal can body according to a fifth aspect of the invention, a synthetic resin film having a printed layer formed on one surface and an adhesive layer formed on the other surface is formed of a synthetic resin film via the adhesive layer. The upper end of the synthetic resin film is bonded to a position where the opening end of the can body is exposed, and the upper end, the lower end, and both ends in the circumferential direction of the synthetic resin film. , And all of the printing layers are covered with a protective coating.

Therefore, as in the first to fourth aspects of the invention, the end of the synthetic resin film is prevented from being damaged, and the end of the synthetic resin film is peeled off from the can body. There is no. Moreover, according to the fifth aspect of the present invention, even if the printed layer is not covered with the synthetic resin film, the entire printed layer is covered with the protective film, so that the printed layer is not damaged.

A metal can body according to a sixth aspect of the present invention is the metal can body according to any of the first to fifth aspects, wherein the opening end of the aluminum can body including the end face and the upper end of the synthetic resin film are protectively coated. A metal can body coated with is provided. Therefore, similarly to the first to fifth aspects of the invention, the end of the synthetic resin film is prevented from being damaged, and the end of the synthetic resin film does not peel off from the can body. Moreover, in the invention of claim 6, since the end surface of the opening end portion of the aluminum can body is covered with the protective film, it is possible to apply a metal working tool to post-processing such as necking processing that occurs in an aluminum material. Adhesion is prevented.

In the present invention, as the material of the synthetic resin film, a polyester resin such as polyethylene terephthalate resin or polybutylene terephthalate resin, a copolyester resin consisting of a copolymer of polyethylene terephthalate and isophthalic acid, or polyethylene. Alternatively, a polyolefin resin such as polypropylene, a polyamide resin, or a mixture or a laminate of the above resins can be exemplified. In particular, a biaxially stretched film made of a polyester resin such as polyethylene terephthalate resin can be used for heat resistance. It is preferable in terms of transparency, processability, toughness, glossiness and cost. The thickness of the synthetic resin film is preferably 5 to 25 μm, particularly 8 to 15 μm in terms of necking workability, scratch resistance and workability.

Examples of the material for the protective coating include publicly known finish varnishes of acrylic, polyester, epoxy and alkyd resin coatings that are usually used for metal cans. It is applied in consideration of the resistance, necking property and scratch resistance. The thickness of the protective film is preferably 1 to 10 μm, particularly 2 to 6 μm in terms of necking processability and scratch resistance.
Alternatively, an ultraviolet curable coating material may be used.

As the adhesive, a thermoplastic resin or a thermosetting resin can be exemplified, and it is particularly preferable to use a thermosetting resin in terms of necking processability and heat resistance.
The thermosetting resin may be a polyester-based, urethane-based, epoxy-based, acrylic-based, amino-based, etc. alone or a composition prepared by adding a curing agent thereto or a composition prepared by mixing two or more kinds of resins with a metal can. It is applied considering the adhesiveness with the material of the body. Further, when the color tone of the metal can body is concealed and the cleanliness of printing is required, an adhesive containing various pigments may be applied.

As a method of forming the print layer, gravure printing, flexographic printing, etc. can be exemplified. Particularly, the method of forming the print layer by gravure printing has a clear image quality,
It is preferable in that a high-quality printed layer can be obtained. As the ink, a mixture of polyurethane, a vinyl chloride-vinyl acetate copolymer and a homopolymer thereof, or a mixture of these resins with a curing agent such as isocyanate is used.

Further, as the material of the metal can body, aluminum, tin-plated steel plate, tin-free steel, tin-nickel-plated steel plate, a coated plate coated with an organic film on these, a laminated material laminated with a synthetic resin film, etc. Can be illustrated. As a method of forming a can body, a two-piece can such as an impact extrusion method, a draw forming method, a draw-ironing forming method or a method for producing a monoblock can, or a method of joining side seams by welding, bonding or the like is used. Do 3
A method for manufacturing a piece can can be exemplified.

According to the inventions of claims 1 to 5,
The position of adhering the synthetic resin film may be a position where the vicinity of the opening of the can body is exposed, and after post-processing such as necking processing, when the can lid is attached to the metal can body,
The position where the entire exposed part of the metal can body is hidden is
It is preferable in terms of improving the appearance.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings.

Example 1 FIG. 1 is a sectional view of a two-piece metal can body. Although only a part of the cross section of the two-piece metal can body is shown in FIG. 1, it is symmetrical about the center line C. In FIG. 1, a two-piece metal can body 10 has an aluminum can body 12 formed by drawing-ironing, and the can body 12 is provided with a bottom portion 12A at one end thereof in the axial direction (vertical direction in FIG. 1). The other end in the vertical direction is the opening 12B.

On the outer peripheral portion of the can body 12, a synthetic resin film 14 is provided along the entire circumferential direction. A printing layer 16 is formed on the synthetic resin film 14 by gravure printing, and the adhesive layer 1 is formed on the printing layer 16.
7 are formed. With the adhesive layer 17, the synthetic resin film 14 on which the printing layer 16 is formed is attached to the can body 12.
Of the synthetic resin film 14 on which the printed layer 16 is formed, and both ends of the synthetic resin film 14 in the circumferential direction are laminated in layers. In this example, as the material of the adhesive layer 17, a composition composed of three kinds of resins of acrylic type-epoxy type-amino type is used. In addition, as a method of forming the print layer 16, gravure printing is adopted in this embodiment.

The synthetic resin film 14 is adhered to the end face 12C of the open end 12B of the can body 12 with a space L. In this embodiment, the interval L is set to 1 mm. The interval L is set to a size that can be hidden when a can lid (not shown) is wound around the open end 12B of the two-piece metal can body 10.

The printed layer 16 of the synthetic resin film 14
A protective coating 20 is formed on the surface opposite to the surface on which is formed. As shown in FIG. 1, the protective coating 20 is formed only from the end surface 12C of the open end portion 12B of the can body 12 to the upper end portion 14A of the synthetic resin film 14.
The protective coating 20 is formed on the entire circumferential direction of the can body 12 to which the synthetic resin film 14 is adhered. In addition,
In this embodiment, the protective coating 20 is a polyester-based material.
A three-component composition of acrylic-amino type is used.

The two-piece can body 1 according to this embodiment is described below.
The manufacturing method of 0 will be briefly described. The can body 12 having a desired shape is formed by drawing-ironing or the like. On the other hand, the printing layer 16 is formed on one surface of the synthetic resin film 14 by gravure printing, the adhesive layer 17 is formed on the printing layer 16, and the adhesive layer 17 is dried. Next, the synthetic resin film 14 is formed into a film shape in which the size in the upward direction (direction orthogonal to the circumferential direction of the synthetic resin film 14) of FIG. This synthetic resin film 14 is slightly longer than the circumferential length of the can body 12, that is, the synthetic resin film 1
Cut so as to secure the overlap at both ends of 4. In this case, the overlapping length is 5 mm or less in terms of appearance and cost.

Next, the can body 12 is heated by high-frequency induction heating, the synthetic resin film 14 is brought into contact with the outer peripheral surface of the can body 12 from the adhesive layer 17 side, and the periphery of the can body 12 is pressed by a pressure roller. Bond along the entire direction. From the end surface 12C of the open end 12B of the can body 12 after adhesion to the upper end 14A of the synthetic resin film 14, the protective coating 20 is applied in the entire circumferential direction, and then baked and hardened, and then subjected to necking. 2-piece can body 1
Get 0.

<Embodiment 2> FIG. 2 is another embodiment using the can body 12 similar to the above-mentioned Embodiment 1, and as shown in FIG. 2, the end surface of the open end 12B of the can body 12 is as shown in FIG. The two-piece metal can body 10 has the protective coating 20 formed only on the portion of the synthetic resin film 14 that is subjected to post-processing such as necking from 12C, and the other configurations are the same as in the first embodiment.

<Embodiment 3> FIG. 3 is another embodiment using the can body 12 similar to the above-mentioned embodiment 1, and as shown in FIG. 3, the end surface of the open end 12B of the can body 12 is as shown in FIG. This is an example in which the protective coating 20 is continuously formed from 12C to the lower end 12D of the can body 12 through the entire outer surface of the synthetic resin film 14. Further, the protective coating 20 is formed along the entire circumferential direction of the surface of the synthetic resin film 14.

A two-piece can body 10 constructed as described above.
Is the end surface 12C of the open end 12B of the can body 12, the upper end 14A of the synthetic resin film 14, and the lower end 12 of the can body 12.
D and the lower end portion 14B of the synthetic resin film 14, the can body 12
Both ends of the synthetic resin film 14 adhered to the peripheral direction in the circumferential direction are covered with the protective coatings 20, and the can body 12 including the end face is formed.
The end surface 12C and the entire synthetic resin film 14 are covered with the protective coating 20. In addition, in the above Examples 1 to 3, the adhesive layer 17 may contain a pigment such as white or pearl in order to improve the color tone of the printing layer 16.

<Embodiment 4> FIG. 4 is another embodiment using the can body 12 similar to that of the above-mentioned Embodiment 3, and as shown in FIG. 4, the can body 12 side of the synthetic resin film 14 is used. The printing layer 16 is formed on the surface opposite to the surface. Also in this embodiment, similarly to the third embodiment, the end face 12C of the open end 12B of the can body 12, the upper end 14A of the synthetic resin film 14, the lower end 12D of the can body 12, and the synthetic resin film 14 are used. Bottom end 14B of the can body 12, and the synthetic resin film 14 adhered to the can body 12 is covered with the protective coatings 20 at both ends in the circumferential direction, and the open end portion 12B of the can body 12 including the end face 12C and the synthetic resin film 14 Is covered with a protective coating 20. In Example 4 of FIG. 4, the synthetic resin film 14 and the adhesive layer 17 may contain a content of white, pearl or the like in order to improve the color tone of the printing layer 16.

In the first to fourth embodiments, the end face 12C of the open end 12A of the aluminum can body 12 is covered with a protective coating in view of the adhesion of the metal material to the tool in the neck-in processing in the subsequent process. However, when a tin-plated steel plate, tin-free steel, or tin-nickel-plated steel plate is used as the material for the metal can body of the can body 12, the end face 12C does not necessarily need to be covered with a protective film. Furthermore, in the above Examples 1 to 4, the synthetic resin film 1 is used.
Although both ends in the circumferential direction of 4 are laminated in a layered manner, they may be spaced apart without overlapping.

[0036]

According to the present invention, the upper end portion of the synthetic resin film is not damaged even when the can body is post-processed such as necking process, flange process or curling process. Since the film does not peel from the can body and the film does not peel as described above, the metal can body of the present invention has excellent retort resistance. Further, according to the inventions of claims 2 and 3, it is not necessary to use a large amount of paint forming the protective film, and it is not necessary to heat the entire can body when the paint is cured. Further, according to the inventions of claims 4 and 5, water or warm water does not enter between the synthetic resin film and the can body, and peeling of the film or corrosion of metal does not occur. Further, according to the invention of claim 5, even if the printing layer is not covered with the synthetic resin film, the entire printing layer is covered with the protective film, so that the printing layer is not damaged. Further, according to the invention of claim 6, adhesion of an aluminum material to a working tool in post-processing such as necking when using an aluminum can barrel is prevented, and continuous production of this kind becomes possible.

[Brief description of drawings]

FIG. 1 is a sectional view of a metal can body according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a metal can body according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a metal can body according to a third embodiment of the present invention.

FIG. 4 is a sectional view of a metal can body according to a fourth embodiment of the present invention.

[Explanation of symbols]

 10 Metal Can Body 12 Can Body 14 Synthetic Resin Film 16 Printing Layer 17 Adhesive Layer 20 Protective Film

Claims (6)

[Claims] 1. A synthetic resin film having a printing layer and an adhesive layer formed on one surface thereof, wherein the upper end of the synthetic resin film is positioned so as to expose the opening end of the can body. A metal can body, which is adhered to the can body via an adhesive, and at least an opening end of the can body and an upper end of a synthetic resin film are covered with a protective coating. 2. The metal can body according to claim 1, wherein a protective coating covers the opening end of the can body and the upper end of the synthetic resin film. 3. The metal can body according to claim 1, wherein a protective coating covers from the opening end of the can body to the synthetic resin film in the portion to be post-processed. 4. The metal can body according to claim 1, wherein the synthetic resin film is covered with a protective coating on the upper end portion, the lower end portion, and both end portions in the circumferential direction. 5. A synthetic resin film having a printed layer formed on one surface and an adhesive layer formed on the other surface, the upper end of the synthetic resin film exposing the open end of the can body. A metal can, which is adhered to the can body in a state of being positioned, and is covered with a protective coating on the synthetic resin film, including the upper end portion, the lower end portion, and both circumferential end portions, and a printing layer. Torso 6. The metal according to claim 1, wherein the metal can body is made of aluminum, and the opening end including the end face of the can body and the upper end of the synthetic resin film are covered with a protective film. Can body.