JPS6382946A - Can-like vessel cover - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to various cans such as beverage coffee cans, soup cans, motor oil cans, edible oil/seasoning cans, and similar containers, ie, raw containers. The present invention relates to a lid constituting a container, and particularly relates to a technique that can improve the opening (opening) characteristics of a lid of a can-like container mainly made of synthetic resin by tearing or suppressed tearing at high temperatures.

[Prior art 1] Concerning the above-mentioned fresh containers, fresh containers mainly made of synthetic resin have been proposed (Japanese Patent Application Laid-Open No. 1983-1999).
39489).

The present inventors have previously proposed the following lid for a living container mainly made of such synthetic resin.

1. For example, an A stand-up material having heat-meltable synthetic resin layers on both sides can be preformed in a flat state or into a dish shape without substantially stretching the AM foil, and then placed in an injection molding machine. It is set in the mold in advance, and the synthetic resin is injected on the outside side as the lid, and the injection is simultaneous (integral).
By molding.

It constitutes a can-like container lid.

According to this, in the heat-meltable synthetic resin layer on the AQ foil,
The adhesive strength is high because the molten resin is laminated by injection.
It has the advantage that the laminated part of the lid does not peel off due to heat history such as retort processing, and the produced raw container has high drop strength. It has the advantage of being smaller in number and lower in cost.

Although it is possible to make a similar lid by injection molding a synthetic resin sheet in a separate process onto An foil, which has heat-meltable resin layers on both sides, and pasting these with adhesive. Post-bonding methods that use such adhesives increase the number of steps, which increases costs, and the food hygiene of the adhesive becomes a problem, and it easily peels off due to the heat history during retort processing, etc. There are various difficulties.

In the injection-molded upper lid, the injection synthetic resin layer on the surface of the AL; L foil composite base material is laminated on the flap part around the lid, on the body of the container having a similar heat-meltable synthetic resin layer surface. The heat-meltable synthetic resin layer on the opposite side allows for installation by heat sealing, for example, and the lid panel inside the flap part of the lid is not laminated with an injection synthetic resin layer. In other words, A stand-up composite base material (multilayer base material) having heat-meltable resin layers on both sides.
A part of the score (cutout part) is formed in a band-like and, for example, oval shape, with the part of the score exposed, and one end of the handle part is attached to a base part made of an injection resin layer inside this part of the score. By fixing the handle and lifting the other end of the handle upward, one end of the handle moves inward to the can, and its tip causes tearing or suppressed tearing of the multilayer base material of a part of the score. is cut, and the injection-molded top lid is thereby opened.

However, in a raw container with such an injection-molded lid attached to the body, for example, in winter, it is difficult to open the can with the contents stored in the body, such as coffee or soup, hot. If a synthetic resin with high yield strength, such as an olefin resin, is used in the multilayer base material in a part of the score, even if the aluminum foil layer in the multilayer base material is cleaved, the resin layer will not break. , do not cleave at the same time when opening the can,
Sometimes elongation occurs and the cutting as a whole is not successful.

[Problem 1 to be Solved by the Invention It is an object of the present invention to solve these problems and provide a can-like container lid with improved opening characteristics.

In addition to improving such opening characteristics, the present invention also aims to improve the can drop strength, which is required to be provided above the synthetic resin can-like container CM to which the present invention is applied. shall be.

Other objects and novel features of the present invention will become apparent from the description herein and the accompanying drawings.

[Means for Solving the Problems] The present invention provides a can-like product in which an outer layer is formed by laminating a resin layer by injection molding on an aluminum foil composite base material having heat-meltable synthetic resin layers on both sides. A can-like container lid characterized in that the composite base material is configured such that the yield strength of the aluminum foil is greater than the yield strength of the double-sided synthetic resin layer at the temperature when the can is opened. .

[Function 1] To describe the function of the present invention together with an example, a score part is formed by laminating a synthetic resin layer on the outside as a lid by injection molding on an aluminum foil composite base material having heat-meltable synthetic resin layers on both sides. In the can-like container lid formed by forming the aluminum foil, the yield strength of the aluminum foil is larger than the yield strength of the double-sided synthetic resin layer of the aluminum foil composite base material at the temperature when the can is opened. If the composite base material is configured so that the thickness of the double-sided resin layer is balanced in relation to the thickness of the single-sided resin layer, the cutting strength of the multilayer base material of the score part when opening the can at high temperature is reduced. of,
At the same time as the aluminum foil is cut, the synthetic resin on both sides is cut at the same time without elongation, which improves the opening property of the lid, especially the can opening property at high temperatures. will improve.

[Example] Next, the present invention will be described based on an example shown in the drawings.

Fig. Ei1 shows a plan view of an example of the lid body before the handle is attached, which is the previous proposal by the present inventors, and Fig.
- Ii, Ia sectional view is shown.

The lid main body 1 consists of a flap section 2 at its peripheral end and a panel section 3 inside the flap section.

The lid main body 1 has, on the multilayer base material 4 (on the outer side as a lid),
The injection resin layer 5 is made up of a vI layer.

The injection resin layer 5 is laminated on the panel part 3,
Therefore, a score portion (cutout portion) 6 is provided in which the multilayer base material 4 is exposed. As shown in FIG. 1, the score portion 6 is preferably formed entirely in a curved shape. FIG. 1 shows an example of an elliptical shape. As will be described later, the opening of the lid is performed along the outer peripheral edge 7 of this band-shaped score portion 6. A semicircular pedestal part 8 for attaching a handle part is provided inside the score part 6 and on the left side in FIG. 1, and further,
A f-shaped extension portion 9 extending from the pedestal portion 8 is provided. The D-shaped interior surrounded by the extension part 9 and the pedestal part 8 is an exposed part 10 of the multilayer base material 4, similar to the score part 6.

Regarding this D-shaped portion 10, in the above embodiment, the multilayer base material 4
Although the injected resin layer 5 is an exposed portion, the injection resin layer 5 may be a vI layer.

A mailbox 11 is erected on the pedestal part 8.

Although the embodiment shown in FIG. 1 shows an example in which two postboxes 11 are installed upright, the number of postpos 11 may be one.

FIG. 3 shows a plan view of an example of the lid 13 in which the handle portion 12 is attached to the lid main body 1 shown in FIG. 1, and FIG. 4 shows a sectional view taken along the line II--II of FIG. 3.

The attachment of the handle part 12 to the post 11 is performed, for example, by attaching the handle part 12 to the post 11.
For example, circular through or non-penetrating holes are made in the tip of the post 11 in the number corresponding to the number of posts 11, the head part of the post 11 is fitted into the hole, and the fitting contact part is melted by ultrasonic welding. , this can be done by integrating.

The handle part 12 is made of synthetic resin, and as described above, the handle part 12 is made of synthetic resin.
It is dammed by later arrival.

FIG. 5 shows a plan view of a lid made by attaching a handle 14 different from that shown in FIG. 3 to the upper lid main body 1 similar to that shown in FIG. When a straw is inserted into the can through the hole 140 through the multilayer base material 4, the contents of the can can be taken in through the straw as well. FIG. 6 shows a sectional view taken along the line m-m in FIG. 5, and FIG. 7 shows the lid 15 shown in FIG. A perspective view of an example in which a bottom lid 17 is attached to the lower part of the moon part 1B to constitute a container for one living is shown.

8 is a plan view of the upper cover after opening, and FIG. 9 is a sectional view taken along the line IV-IT in FIG. 8.

That is, an example of the opening of the upper lid will be explained with reference to FIG. 4. As shown by the arrow in FIG. The lid is opened along the outer peripheral edge 7 of the score portion 6 by inserting and tearing the material 4 and then continuing to pull the handle portion 12 to the right in the figure.

In the can-like container lid of the present invention, according to the score part 6,
The lid panel portion 3 may be separated into an open portion and other portions, or the score portion 6 may be formed into a curved shape such as an ellipse with an appropriate width, or the score portion 6 may be formed as close to the upper lid flap as possible. It can be installed near part 2, so
Various opening properties can be obtained.

Next, the multilayer base material which is the structure of the present invention will be explained.

The multilayer base material 4 used in the present invention is a barrier base material 19
It has heat-meltable synthetic resin layers 20 and 21 on both sides.

The gas barrier base material 19 needs to have so-called gas barrier properties that prevent permeation of oxygen, moisture, and the like.

Examples of the gas barrier substrate 18 include metal foil, sheet, film, and the like.

A typical example of metal foil is aluminum foil (hereinafter simply referred to as aluminum foil), and the present invention particularly relates to a can-like container lid made of this aluminum foil as the gas-resistant base material 19. Examples of other gas barrier substrates 19 include sheets and films of saponified ethylene-vinyl acetate copolymers, polyvinylidene chloride, polyamides, polyacrylonitrile, and the like.

As mentioned above, the electrode container lid according to the present invention is designed to be opened by tearing or cutting the multilayer base material 4 having the gas barrier base material IS, and is easy to open and can be used as a product. Gas barrier substrates such as aluminum foil 1
It is desirable that the thickness of 9 be 50p or less, preferably 9 to 30p.

In addition, by having such a thickness, complete incineration is possible, and the incineration calories are 5,000 to 6,000.
kcal/kg, and can solve the problem of empty can disposal.

The multilayer base material 4 has a heat-meltable synthetic resin (hereinafter referred to as the resin layer of Section 1) 20 and 21 on both or one side of the gas barrier base material 19. The embodiment shown in the drawings shows an example in which the first synthetic resin layer is formed on both sides.

If the ridge strength of the first synthetic resin layer is greater than that of the aluminum foil, the aluminum foil will tear first, and when the score is partially cleaved, the synthetic resin layer will stretch, resulting in poor opening properties.

When a thick aluminum foil is used as the composite base material, the opening properties are better than when a thin aluminum foil is used.

As an example below, aluminum foil 15p, 30. The results using the composite base material are shown in FIG. 15 and Table 1.

1 70μ 15 70le II
70 AL30 50g (1) Tensile properties of composite base material (Figure 15) In composite base material work, the yield strength of aluminum foil is small, so even if the aluminum foil is cut, the resin will not be cut and the elongation of the composite base material will be low. growing.

In the base material 11 (A thickness of 30 IL), the yield strength of the aluminum foil is sufficiently greater than that of the resin layers on both sides, so when the aluminum foil is cut, the resin layer is also cut by the impact at the same time, so that the elongation is small.

(2) Can opening test results (Table 1) When we conducted a can opening test using the above composite base material, we found that with composite base materials, the composite base material stretches when opening the can, resulting in poor can opening.
In particular, when opening a can at high temperatures, it becomes more prone to stretching and becomes impossible to open.

Since the composite base material 11 does not stretch when the can is opened, the can can be opened easily even at high temperatures.

Table 1 0...Good Δ...Poor ×...Unsatisfactory The lid of each electrode container according to the present invention is attached to the body 1B of each electrode container as described above. This body portion 16 also has a similar resin layer surface.

The first resin layer on the attachment side to the body of the lid is an inner layer 20, and the resin layer 5 (hereinafter referred to as the resin layer in Section 2) laminated on the multilayer base material 5 by injection molding or the like. When the first resin layer on the side to be heat-sealed is the outer layer 21, the multilayer base material 4 according to the present invention preferably has inner and outer layers 20 and 21, as shown in the above embodiments. . Due to the presence of this outer layer 21, a lid with high adhesiveness can be formed by thermal fusion with the second resin layer 5.

As the resin constituting the first resin layers 20 and 21, a resin that melts by heat, typically a polyolefin resin, is used.

The inner and outer layers 20 and 21 may be made of the same resin, or may be made of different resins.

When forming the first resin layer 20, 21 on the gas barrier substrate 19, it can be formed with or without an adhesive resin layer such as an adhesive or a film-like hot melt adhesive.

The thickness of the first resin layer 20, 21 is preferably 100 μl or less on one side in order to achieve the object of the present invention.

However, the aluminum foil layer has 20 or more seats, preferably 25 to 20 seats.
It costs 50 ru.

The container lid for each electrode according to the present invention can be obtained, for example, as follows.

This will be explained with reference to FIGS. 10 to 12.

As shown in FIG. 10, the multilayer base material 4 is inserted into the guide member (stripper plate) 22. This can be done while adsorbing the multi-layer material 4 onto the moving cylinder 23 of the robot.

As shown in FIG. 11, the multilayer base material 4 is fixed within the stripper plate 22 to prevent displacement, and the mold is clamped as shown in FIG. 12. As a result of this mold clamping, the ends of the flat (two-dimensional) multilayer base material 4 are bent within the mold (core mold, receiving mold) 24 as shown in FIG. Molten resin is injected from the gate 2B of a mold (cavity mold, injection mold) 27 having a gate 26 into a cavity (mold space) 28 formed between the core mold 24 and the cavity mold 27. A second resin layer 5 made of the above-mentioned molten resin is laminated on the surface of the multilayer base material 4, a post 11 is erected on a pedestal part 8 made of this resin layer 5, and a lid having an extension part 9 is provided. A main body 1 is obtained.

In this way, by injecting the synthetic resin 5 onto the multilayer base material 4, the flap part 2 and the panel part 3 are formed, and the pedestal part 8 and the pedestal are made of the injected resin layer 5 and are integrally formed. The lid body l has a post 11 erected on the part 8 and an extension part 9 extending from the pedestal part 8, and further has a notch part 6 that can be formed in the same shape during injection molding. can be obtained.

The handle portion 12 is preferably manufactured from the same resin in a separate process from the injection molding described above, and attached to the post 11 by ultrasonic welding.

The lid main body 1 of the can-like container lid of the present invention can be obtained as described above, but in the present invention, subsequent research on such injection molded lids has revealed that the following method is even better. This will be explained with reference to FIGS. 13 and 14.

A disc-shaped multilayer base material 4 as shown in FIG. A container having a flange portion 34, a body wall portion 35, and a bottom portion 36 without substantially stretching the multilayer base material 4 by inserting a mold 31 and absorbing the excess portion of the multilayer base material in the vertical direction as wrinkles 33. A preformed multilayer base material 37 is used.

This preformed multilayer base material 37 is set in an injection mold 38, and the injection resin 5 is injected outward as a lid.

During injection, the multilayer base material 37 is pressed against the mold 38 by resin pressure during injection molding, and the wrinkles 33 are smoothed.

This prevents irregular large wrinkles that occur in the multilayer base material 4 that occurs in the case of the flat insert molding method shown in FIGS. 10 to 12, and as shown in FIG. When the flange portion 2 made of the resin layer 2 is welded to the body portion 16 of each electrode container by high-frequency induction heating, it is possible to prevent seaming defects from occurring.
In addition, it is possible to prevent the gas barrier base material 19 of the multilayer base material 4 from being cut due to local heating, and since the preform is performed without substantially stretching, thin AI foil can be used, and the resulting molded The A-disappearance in the product can also provide advantages such as a uniform thickness.

Various types of resins can be used for the injection resin 5 used in the present invention, including synthetic resins such as polyolefin-based synthetic resins such as polypropylene and ethylene-propylene copolymer, which have excellent heat resistance against high temperatures during retort sterilization. An example is resin.

An inorganic filler may be mixed with the injection resin. Mixing an inorganic filler has the following advantages.

■ The dimensional stability of each electrode container is improved, and the yield rate is reduced, which is advantageous.

■ Improved heat resistance and increased heat distortion temperature, which is advantageous for retorting.

■ Burned calories are reduced, and combustion furnaces are not damaged, which is advantageous in solving empty can disposal problems.

■ It can provide rigidity, which is advantageous for product distribution.

■ Good heat conduction, which is advantageous for retorting.

■ Cost can be reduced.

As the inorganic filler, any filler that is widely used in the fields of synthetic resins and rubbers may be used. These inorganic fillers are preferably inorganic compounds that have good food hygiene properties, do not react with oxygen and water, and do not decompose during crosstalk or molding. Examples of the inorganic filler include compounds such as metal oxides, hydrates (hydroxides), sulfates, carbonates, and silicates;
It is broadly classified into these double salts and mixtures thereof. Typical examples of such inorganic fillers include aluminum oxide (alumina), its hydrates, calcium hydroxide, magnesium oxide (magnesia), magnesium hydroxide, zinc oxide (zinc white), red lead, and lead such as white lead. oxide, magnesium carbonate, calcium carbonate, basic magnesium carbonate, white carbon, asbestos, mica, talc,
Glass fiber, glass powder, glass peas, clay, diatom ±, silica, wollastonite, iron oxide, antimony oxide, titanium oxide (titania), lithopone, pumice powder, aluminum sulfate (gypsum, etc.), silica zirconium,
Examples include zirconium oxide, barium carbonate, dolomite, molybdenum disulfide and iron sand. Among these cicada fillers, those in powder form preferably have a diameter of 20 microns or less (preferably 10 microns or less). In addition, fibrous materials have a diameter of 1 to 500 microns (preferably 1 to 500 microns).
~300 microns) with a length of 0.1 to 6 mm
(preferably 0.1 to 5 mm) is desirable. Furthermore, the diameter of the flat plate-like one is 30 microns or less (preferably 1 micron or less).
(0 micron or less) is preferred. Among these inorganic fillers, those in the form of flat plates (flake) and those in the form of powder are particularly suitable.

In addition, various additives such as pigments may be added to the injection resin.

[Effects of the Invention] According to the present invention, when the can is opened at high temperature, the aluminum foil is cut and at the same time the synthetic resin layer on both sides, which is easy to stretch, is also cut by the impact, making it easier to open the lid. Became.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the upper lid body, Fig. 2 is a sectional view taken along the line I-1 in Fig. 1, Fig. 3 is a plan view of the upper cover, and Fig. 4 is Fig. 3 II--
5 is a plan view showing another example of the upper lid, FIG. 6 is a sectional view taken along line m-m in FIG. 5, FIG. 7 is a perspective view of an example of a can-like container, and FIG. Top lid-side plan view after can, Figure 9 is 2
Figure 88 rV-IV line sectional view and Figures 10 to 12 respectively explain the lid forming process.・ψ・Synthetic resin layer 6a・・Score part 8・・Pedestal part 9・・Extension part 12・・Handle part 13・Fist・・Lid 14・・Handle part Patent applicant Showa Denko K.K. agent Yoshihiro Sato, Patent Attorney Figure 1, Figure 3, e 'IIL5, Figure 8, Figure 9, Figure 12, Figure 15

Claims (1)

[Claims] In a can-like container lid formed by laminating a resin layer by injection molding on an aluminum foil composite base material having heat-meltable synthetic resin layers on both sides to form an outer layer, the double-sided synthetic resin layer at the temperature when the can is opened. A lid for a can-like container, characterized in that the composite base material is configured such that the yield strength of the aluminum foil is greater than the yield strength of the aluminum foil.