JPH0126586Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) The present invention relates to an easy-to-open container lid, and more particularly to an easy-to-open container lid having an opening shape that is excellent in impact resistance and ease of drinking the contents. (Prior art and its problems) Conventionally, as a type of easy-to-open container lid, a can end member is provided with a pre-formed opening, and the outside of the can end member covers the opening and is in close contact with the periphery of the opening. It is known that the seal consists of an easily peelable opening piece applied in this way. The close contact of this opening piece to the can end member is
This is done using pressure-sensitive adhesives or heat-sealing using thermoadhesive resin, but in either case, if poor adhesion or peeling occurs between the opening piece and the area around the opening, it is said to be a seal failure due to leakage. This will cause serious problems. In this type of easy-open container lid, many proposals have already been made to protect the opening cut edge and to improve the pressure-resistant adhesion between the opening piece and the area around the opening. There are almost no proposals to protect the bonded parts from impacts such as drops. (Purpose of the invention) Therefore, the purpose of the invention is to provide an opening with an opening shape that is excellent in ease of drinking the contents, and that can protect the adhesive part between the opening piece and the area around the opening from shocks such as drops. To provide an easy-to-open container lid. Another object of the present invention is to maintain an easy-to-open container lid that prevents adhesive deterioration and peeling between the opening piece and the area around the opening, even if a drop impact is applied to the end of the can. is to provide. Still another object of the present invention is to provide an easy-to-open container lid that reliably prevents the protection of the opening cut edge from being destroyed even when the container is subjected to impact due to the above-mentioned drop or the like. (Means for Solving the Problems) According to the present invention, a can end member is provided with a pre-formed opening, and a can end member is provided on the outside of the can end member so as to cover the opening and come into close contact with the periphery of the opening. In an easy-to-open container lid consisting of an easily peelable opening piece, the can end member has a long dimension in the radial direction and has an opening whose periphery is tapered outward; The size and shape extend from the inside of a concentric circle with a diameter 0.35 times the outer diameter of the seaming member to the vicinity of the outer periphery of the can end member, and the portion defined by the outline of the opening and the circle has a diameter of 10 mm. Provided is an easily openable container lid characterized by having a shape that encloses a circle. (Function) The easy-to-open container lid of the present invention has a long dimension in the radial direction and an opening whose periphery protrudes outward in a tapered shape. The size and shape extend from the inside of a concentric circle with a diameter of 0.35 times that of the container end member to the vicinity of the outer periphery of the can end member, and the portion defined by the outline of the opening and the aforementioned circle contains a circle with a diameter of 10 mm. A notable feature is that In other words, the easy-to-open container lid of the present invention is
By specifying the size and shape of the opening as described above, it is not only easy to drink the contents, but also prevents the opening piece from adhering to the area around the opening even if a drop impact is applied to the end of the can. Deterioration and peeling are prevented,
An easy-to-open container lid that maintains the seal is provided, and this effect is achieved by making the opening periphery protrude outward in a tapered shape, so that the opening piece adhered to the tapered periphery can be easily opened. If the stress applied between the two is not a peeling force but a shear stress, the stress becomes even more significant. (Description of Preferred Embodiments) In FIGS. 1 to 3 showing the structure of the easy-to-open container lid of the present invention, this container lid includes a lid member generally designated by 1, a (can end member) and generally designated by 2. It consists of an opening piece. This can end member 1 is made of a rigid material, such as a painted metal plate,
At a certain position in its central part, it has a pre-formed opening 3 for taking out the contents. This opening 3 is
It has a tapered peripheral portion 9 whose periphery is tapered outward. A flange 4 is provided around the periphery of the can end member 1 for double seaming between the can end member 1 and the can body (not shown). The opening piece 2 is provided on the outside of the can end member 1 so as to cover the aforementioned opening 3 and to be in close contact with the periphery of the opening. That is, an adhesive layer 5 is provided between the opening periphery of the can end member 1 on the side where the opening piece 2 is applied and the opening piece 2, and this adhesive layer 5 connects the can end member 1 and the opening piece. 2 is joined and sealed. Adhesive layer 5
is a pressure-sensitive adhesive, and the can end member 1 and the opening piece 2 may be joined under pressure, and the adhesive layer 5 is a heat-adhesive thermoplastic resin layer, and both are bonded together under pressure. The bonding may be performed under heating. In FIG. 3 showing the shape of the opening 3 of the easy-to-open container lid of the present invention, this opening has a long dimension in the radial direction of the can end member 1; It has a size and shape that extends from the inside of a concentric circle A having a diameter of D ₂ =0.35D ₁ to the vicinity of the outer periphery of the can end member 1, where the outer diameter of the opening 3 is D ₁ . A portion 6 defined by the outline B and the circle A
has a shape that encloses a circle C with a diameter of 10 mm. First, in terms of ease of opening, ease of drinking the contents through the opening 3, and ease of pouring out the contents, the opening 3 is longer in the radial direction of the can end member 1, as shown in FIG. It is important to have the dimensions. According to the results of sensory tests conducted by the inventors,
It has been found that the best ease of drinking the contents can be obtained when an opening with a size and shape extending from the inside of circle A with a diameter of D ₂ = 0.35D ₁ described above to near the outer periphery of the can end member is provided. Ta. On the other hand, this canned product with an easy-to-open container lid,
The results of an inverted drop impact test showed that a high impact force was locally concentrated at a specific location on the container lid (appearing as a navel-shaped protrusion on the opening piece), and this location was
Although it varies slightly depending on the shape and size of the opening,
It was confirmed that the opening was located in the center of the can end member, that is, in the area surrounded by the circle A with a diameter of D ₂ =0.35D ₁ described above (actually, it was an opening piece that covered this). However, if the adhesive layer 5 connects the unsealing piece 2 and the opening periphery adjacent to or close to this local high impact force generation area, this impact force may cause adhesive failure or peeling. Leakage can easily occur. In this way, if all the openings 3 are located outside the circle A, even though there is no risk of adhesive failure due to impact, the disadvantage is that the opening shape itself makes it difficult to drink the contents. Yes, opening 3
If the inner edge of the is located inside circle A, even though satisfactory results may be obtained in terms of ease of drinking the contents, adhesive failure due to impact and associated leakage may occur. There is a fatal flaw that is easy to occur. According to the present invention, such a defect causes the opening periphery to protrude outward in a tapered shape, as described above,
By making the shape and dimensions of the opening specific as described above, this problem can be solved very effectively. That is,
A portion 6 defined by the circle A and the outline B of the opening 3 having a peripheral portion projecting outward in a tapered shape.
By making the shape enclosing a circle C with a diameter of 10 mm, the adhesive will not break at the joint between the opening piece 2 and the can end member 1 even when a high impact force is locally concentrated due to a fall, etc. This prevents the occurrence of peeling or peeling. If the diameter of the maximum circle included in the above-mentioned portion 6 is smaller than 10 mm, leakage will occur even in the event of a drop impact that must be practically withstood during the distribution stage, as shown in the example described later. In the present invention, the fact that setting the diameter of the inner circle C of the opening portion 6 defined by the outline B of the opening 3 and the circle A to be 10 mm or more is effective in preventing leakage due to impact can be confirmed by repeated experiments. This was discovered empirically, and the reason has not yet been elucidated. However, as already detailed,
The localized impact force is concentrated on the opening piece 2 in the area surrounded by the circle A, and the protruding deformation of the opening piece due to this impact force occurs at a maximum diameter of about 10 mm. It is presumed that by setting the diameter of the inner circle C to 10 mm, deformation due to impact is prevented from reaching the joint between the opening piece 2 and the can end member 1. In the present invention, by making the opening periphery protrude outward in a tapered shape and by making the opening 3 have the shape described above, it is possible to not only prevent adhesive failure and peeling between the opening piece 2 and the can end member 1. Therefore, the effect that the cut edge covering at the opening of the can end member 1 is also safely protected regardless of the impact force is achieved. For example, as shown in FIG. 4 showing the conventional example,
A protective resin layer 7 is pasted on the inside of the can end member 1, that is, on the side opposite to the side where the opening piece 2 is provided, to protect the opening cut edge 8 of the can end member 1 from corrosion. , the above-mentioned local impact force causes the opening piece 2
In addition to the above-mentioned leakage, if a concentrated occurrence occurs in
The protective resin layer 7 is broken or cracks are generated in it, and metal elution from the cut edge 8 and corrosion of the cut edge 8 easily progress. In the present invention, by setting the diameter of the inner circle C to 10 mm or more, it is possible to prevent local impact force from being applied to the protective resin layer 7, and effectively prevent the protective resin layer 7 from breaking or cracking. It's something you get. Furthermore, in the present invention, since the opening piece 2 is bonded at the tapered peripheral part 9, even if the opening piece 2 is deformed protrudingly due to a drop impact, there is a gap between the opening piece 2 and the peripheral part 9. The stress applied to the joint becomes a shear stress rather than a peeling force, and as a result, peeling of the bonded portion is effectively suppressed. The tapered protrusion around the opening can be formed by engaging and pressurizing the can end opening with a tapered punch and die after application of the opening piece. In the present invention, the shape of the opening 3 can be freely changed within the range that satisfies the various requirements described above. For example, shapes such as a circle, an ellipse, an oval, a raindrop shape, an oval, a gourd shape, etc. may be used, but of course, the opening shape in the present invention is not limited to these. Generally speaking, the width of the tapered peripheral portion 9 is as follows:
in the range 0.5 to 5 mm, especially 1 to 3 mm, and the protrusion angle from the plane is generally 10 to 40 degrees, especially 15
It is desirable that the angle is in the range of 30 to 30 degrees. In the present invention, the can end members are made of treated steel plates such as light metal plates such as aluminum, tinplate, aluminum plated steel plates, chrome plated steel plates, and electrolytic chromic acid treated steel plates, in an unpainted state.
Alternatively, it is used after being coated with a thermosetting resin paint and/or a thermoplastic resin paint that is known per se. The opening piece is made of a material that is flexible and has gas barrier properties, such as aluminum foil, tin foil, iron foil, metal foil such as steel foil, biaxially oriented polyester film, biaxially oriented polyamide (nylon), etc. )
A film, a biaxially oriented polypropylene film, or a laminate of these is used.
The above-mentioned pressure-sensitive adhesive layer, heat-adhesive thermoplastic resin layer, paint layer, etc. may be provided on the side of the can end member of these opening pieces. (Example) The present invention will be explained in detail below with reference to Examples. Example A 0.23 mm thick electrolytic chromic acid treated steel plate (Tein Free Steel, TFS; heat treatment grade T4CA) with a 5 μm thick paint film coated and baked with a mixed paint of epoxy resin and phenol resin on both sides was prepared. . The above-mentioned painted plate was molded to create a container lid-shaped member with an outer diameter of 62 mm.
An SBR-based sealing compound was applied and dried to fabricate a can end member. An oval opening with a major axis of 27 mm and a minor axis of 10 mm was bored in the flat part of the can end member using a punch and a die to provide a spout. The opening was positioned so that the center of the oval was 6.5 mm away from the center of the can end member. 50μm thick polytetramethylene (terephthalate/isophthalate) film (melting point 170℃)
It has a similar shape to the opening and a slightly larger outer circumference, and the center part is punched into a 2 mm wide annular shape with a hole of the same size as the opening. I placed it. Thereafter, the film was pressed onto the periphery of the opening with a pressure of 5.3 kg/cm ² using a brass pressing tool, and at the same time the temperature of the periphery of the opening was raised to 200°C using high-frequency induction heating. The film was fused to the can end member. A mixed resin of epoxy resin and phenolic resin (the weight ratio of epoxy resin/phenolic resin is
75/25) A 50 μm thick single-sided coated aluminum foil with a 5 μm thick resin coating coated with a solution and baked at 230° C. for 30 seconds was first prepared. Next, a biaxially oriented polyethylene terephthalate film with a thickness of 50 μm was attached to the non-painted side of the single-sided coated aluminum foil using an adhesive to form a laminated film with a width of 18 mm.
An opening piece was prepared by cutting to a length of 45 mm. After placing the unsealed piece so that the coated surface covers the heat-adhesive resin layer of polytetramethylene (terephthalate/isophthalate), a pressure of 10 Kg/cm ² is applied using a presser made of heat-resistant rubber. At the same time, the area around the opening was heated to 250°C using high-frequency induction heating, and the coating film applied to the opening piece and the 50 μm polytetramethylene (terephthalate/ isophthalate) and a thermoadhesive resin layer. A 20 μm thick polypropylene film with a 10 μm thick acrylic adhesive layer on one side is 16 mm wide.
A protective coating film is formed by cutting to a length of 31 mm, and the adhesive layer is placed in the opening of an easy-to-open container lid so that the inner surface of the container lid is in contact with the adhesive layer. The opening piece and the protective coating layer were pressed together at 5 kg/cm ² using a pressing tool made of rubber elastic material so as to be in close contact with the inner coating of the lid and at the same time with the coating layer of the opening piece. An easy-to-open container lid was manufactured. Next, using a punch and a die, the opening periphery is made to protrude outward in a tapered shape to obtain an easy-to-open container lid having an opening periphery shape with a width of 2 mm and a protruding angle of 25 degrees from the plane. Created. After producing the easy-to-open container lid of the present invention through the above steps, a 200 mm inner diameter 52.3 mm container lid made of a 0.22 mm thick TFS plate with a regular container lid double-sealed on the other end is prepared. A bottled fruit juice drink was prepared by hot filling an adhesive case for a gram can with orange juice, and double-sealing the easy-open container lid of this example to the case so that the outer diameter was 55 mm. . Comparative Example 1 A bottled fruit juice drink was produced in the same manner as in Example except that the periphery of the opening was formed flat without protruding in a tapered shape. The cans prepared in Example and Comparative Example 1 were subjected to a drop test, and the results are shown in Table 1. Leak Test Leakage of the contents was tested when the cans were dropped onto a steel plate from different heights with the lid with the opening piece facing down. Observation of the protective resin layer on the cut edge After storing the canned product subjected to the drop test at 37℃ for one year, use a can cutter to separate the lid with the opening piece from the case to protect the cut edge on the inner surface of the opening. The coating state of the resin layer was observed.

[Table] Comparative Example 2 A bottled fruit juice drink was produced in the same manner as in Comparative Example 1, except that the minor axis of the opening was 4 mm and 8 mm. The results of the drop test are shown in Table 2.

【table】 [Brief explanation of drawings]

FIG. 1 is a plan view showing the easy-to-open container lid of the present invention, and FIG. 2 is a line b-b of the container lid in FIG.
FIG. 3 is an explanatory diagram of the opening shape of the easy-open container lid of the present invention, and FIG. 4 is a sectional view of a conventional container lid. Reference number 1 is the can end member, 2 is the opening piece, 3 is the opening, 4 is the flange, 5 is the adhesive layer, 6 is the outline of the opening, the part delineated by B and circle A, 7 is the protective resin layer , 8 indicates the cut edge, and 9 indicates the peripheral portion of the tapered opening.

Claims (1)

[Claims for Utility Model Registration] From a can end member having a pre-formed opening and an easily peelable opening piece provided on the outside of the can end member so as to cover the opening and come into close contact with the periphery of the opening. In the easy-to-open container lid, the can end member has a long dimension in the radial direction and has an opening whose periphery is tapered outward, and the opening is 0.35 times larger than the outer diameter of the seamed outer diameter of the can end member. It has a size and shape that extends from the inside of a concentric circle with double the diameter to the vicinity of the outer periphery of the can end member, and the part defined by the outline of the opening and the aforementioned circle has a shape that includes a circle with a diameter of 10 mm. An easy-to-open container lid characterized by: