JPH0520692Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention relates to a sealing structure for a cap in a packaging container such as a bottle filled with beverages, foods, medicines, etc.

<Problems to be solved by the prior art and the invention> When it comes to packaging containers such as bottles filled with beverages, foods, medicines, etc., poisonous substances may be mixed in or the contents may be removed before reaching the user. There may be cases where In the case of packaging containers such as bottles that are simply sealed with a closing cap, if the container is re-sealed with a cap after contamination or removal, it is possible that the cap was opened midway and poisonous substances were mixed in, or that the contents It was difficult to judge whether or not it had been extracted.

Therefore, in the past, the cap was shrink-covered with a sealing member made of a synthetic resin non-foamed sheet or film such as a shrinkable non-foamed polyethylene film, and the cap could only be opened after the sealing material was torn and removed. A sealing structure for caps was developed, and it was devised that it was possible to determine whether or not the cap had been opened during the process based on the presence or absence of this sealing material. Publication No. 1987
-Refer to Publication No. 37462, etc.).

However, in the conventional cap seal structure, the sealing member is made of a non-foamed synthetic resin sheet or film with very strong tear strength, such as non-foamed polyethylene film, so even if the sealing material is torn and removed from the cap, It had drawbacks such as being difficult to tear and requiring time and effort to open.

For this reason, there are some products in which the sealing material is provided with a tearing auxiliary part such as a tab protrusion, a perforation, or a notch, so that the tearing auxiliary part can be used to easily tear the sealing material from the cap and remove it. However, forming the tear-assisting parts such as the knob protrusions, perforations, or notches is troublesome, and there are problems such as high processing costs.

In addition, in the case of the above-mentioned non-foamed polyethylene film, even if it has been shrink coated once, when it is reheated, the film will soften and expand, and it can be removed from the cap without tearing the sealing material, and it can be shrink coated again. Therefore, it cannot be said that it has a perfect cap sealing function, and it is insufficient in terms of ensuring safety.

This invention aims to eliminate the drawbacks of the prior art described above and provide a cap sealing structure that has a complete sealing function, allows easy tearing of the sealing material during use, and is inexpensive.

<Means for Solving the Problems> In order to solve the above problems, the cap seal structure of this invention is made of a shrinkable foam sheet or film made of polystyrene-based thermoplastic resin, or a shrinkable foam sheet or film made of polystyrene-based thermoplastic resin. The cap and the neck of the container body below the cap are covered and sealed with a heat-shrinkable sealing material so that re-covering is impossible.

<Function> According to the cap sealing structure of this invention constructed as described above, the sealing material is made of a shrinkable foam sheet or film made of a polystyrene-based thermoplastic resin with low tear strength, or formed using this as the main material. The sealing material can be torn and removed from the cap without forming a tearing aid such as a perforation in the sealing material.

In addition, once a sealing material made of a foamed sheet or film is heated to cover the cap with shrinkage, the bubbles in the foamed sheet or film themselves will shrink, so even if it is reheated, the sealing material will not expand. It can be heat-shrinked so that it cannot be recoated after removal.

Furthermore, when the sealing material is formed of a foam sheet, the cushioning properties of the sealing material can prevent damage or scratches on the cap portion.

<Example> Next, an example of this invention will be described below with reference to the drawings.

In the illustrated embodiment, as a container forming a sealing structure, as shown in FIGS. 1 and 2, a slender neck 10, which is the upper end opening of a cylindrical bottle 1, is connected with a screw-in cap 2. The example shows a sealed case.

3 is a sealing material, which is formed from a shrinkable foamed polystyrene sheet, a thermoplastic resin shrinkable foam sheet, or a film.

The sealing material 3 is shown covering the entire cap 2 from the top surface of the cap 2 to a part of the neck 10 of the bottle 1 adjacent to the lower part of the cap 2, thereby sealing the bottle.

Covering and sealing with the sealing material 3 described above is performed using the sealing material 3.
is placed on the top of the cap 2, and then the sealing material 3 is heated to cover the cap with shrinkage.

This shrink coating step will be explained in detail below with reference to FIGS. 2 to 6.

First, for the sealing material 3, a single sheet or film is used, which is a foamed sheet or film that is cut into a rectangular shape or the like having an area corresponding to the size of the cap 2 to be shrink-covered (see FIG. 3).

The sealing material 3 is placed over the upper surface of the cap 2 attached to the bottle 1, and the flexibility of the sealing material 3 is used to loosely cover the cap 2 from the lower part to the neck 10 (see FIG. 4).

Next, a pair of heating plates 4 each having a semicircular recess 40 corresponding to the outer shape of the neck 10 are brought into contact with the neck 10 directly below the cap 2 covered with the sealing material 3 (see FIGS. 5 and 6). (see figure). The heating plates 4 are formed so that they can be heated as a whole by embedding a heater inside the heating plates 4. The pair of heating plates 4 are brought close to each other from both sides of the neck 10, and the recess 40 of the heating plate 1 is inserted into the entire neck 10. By heating the sealing material 3 along the circumference, the sealing material 3
is thermally bonded in close contact with the neck portion 10.

Next, hot air is blown from above onto the sealing member 3 above the heating plate 4 and covering the cap 2 (see FIG. 6).

Then, the sealing material 3 is thermally shrunk and tightly adheres to the outer shape of the cap 2 without any gaps, thereby sealingly covering the entire cap 2.

Then, if the heating plate 4 is moved away from the neck 10, the blowing of hot air is stopped, and the sealing material 3 is cooled, the sealing material 3 separates the cap 2 from the neck 10, as shown in FIGS. 1 and 2. This means that it is possible to form a cap seal structure that completely covers and seals a portion of the cap.

In the above case, from the bottom of the cap 2 to the neck 1
As a sealing material 3 that covers up to 0, use hot air at 130℃
A shrinkable expanded polystyrene sheet with a thickness of 30 μm and a basis weight of 34 g/m ² , which shrinks by 40% in the extrusion direction and 18% in the direction perpendicular to the extrusion direction when heated for 15 seconds, was used at 150°C. The heating plate 4 heated to
After making contact with the sealing material 3 and thermally adhering it in close contact with the neck 10, hot air at 260° C. is blown from above onto the portion of the sealing material 3 that is above the heating plate 4 and covers the cap 2. , the sealing material 3 was heat-shrinked.

As a result, sealing material 3 connects cap 2 to neck 1.
It was possible to obtain a good sealing structure of the cap 2 in which part of the cap 2 was completely covered and sealed.

The shrinkable foam sheet or film forming the sealing material 3 described above is made of polystyrene-based thermoplastic resin, has good shrinkability when heated, and has good shrinkability when the sealing material 3 is removed. It cannot be recoated afterwards.

The sealing material 3 is mainly made of a foamed sheet or film made of polystyrene-based thermoplastic resin, with various thermoplastic materials such as polystyrene, high-impact polystyrene, polypropylene, polyethylene, and ethylene-vinyl acetate copolymer on one or both sides. It is also possible to use a laminated layer of non-foamed films made of resin. In order to laminate the above-mentioned non-foamed film onto a foamed sheet or film, there is a method of laminating the sheet or film at the same time as the forming of the sheet or film by co-extrusion, and a method of laminating the previously manufactured foamed sheet or film and the non-foamed film using a thermal adhesive. There is a method of adhesion and lamination with intervening materials.
The thermal adhesive used for this thermal bonding is made of a highly flexible synthetic resin that has good adhesion to both the foamed sheet or film and the non-foamed film, and is easily deformed when covered with shrinkage. For example, adhesives made of ethylene-vinyl acetate copolymer resin are suitable.

The shrinkability of the foamed sheet or film is imparted by stretching during extrusion molding of the foamed sheet or film, or by stretching after molding.

The sealing material 3 is cut into a certain area according to the size of the cap 2, and the shape of the cut sealing material 3 is rectangular so that there is no waste of material and the cutting process is easy. However, if it is formed into a circular or other shape to match the shape of the cap 2, the excess sealing material 3 will not be distorted around the neck 10 when it is shrink-covered, and the appearance will be improved.

Further, the shape and structure of the bottle 1 and cap 2 to be shrink-covered with the sealing material 3 are not limited to those shown in the drawings, but can be freely changed.

For example, as the cap 2, in addition to a screw-in type, any cap structure for closing and sealing that is used for various ordinary bottles and packaging containers can be freely applied, such as a snap type or a stopper type.

The bottle 1 to which the cap 2 is attached can be any ordinary packaging bottle made of glass or synthetic resin, or any type of packaging container other than a bottle, even if it has a closure structure with a cap. Ba. ,
Can be applied freely.

Further, as a method of covering and sealing the cap 2 with the sealing material 3, as shown in FIGS. 3 to 6,
The sealing material 3 is thermally bonded to the neck 10 directly below the cap 2 using a heating plate 4, and the sealing material 3 is
By heating and shrinking the part that covers the cap 2, the sealing material 3 can reliably cover and seal the cap 2 and part of the neck 10. Since the heat-bonded part 3 is strongly and tightly bonded to the neck 10, there is no fear that the sealing material 3 will peel off, and there is less possibility that the sealing material 3 will wrinkle or that a gap will form between it and the cap 2. Although the shrinking process is easy and suitable, the method is not limited to the above method and can be carried out by freely changing the method as long as the cap 2 and a part of the neck part 10 can be covered and sealed by heating and shrinking the sealing material 3. It is.

<Effects> According to the cap sealing structure of this invention constructed as described above, a part of the neck of the cap and the bottle is made of a shrinkable foam sheet or film made of polystyrene-based thermoplastic resin, or a shrinkable foam sheet or film made of polystyrene-based thermoplastic resin, or It is coated and sealed with a heat-shrinkable sealing material so that it cannot be recoated after removal, and has the following effects.

In other words, foamed sheets or films made of polystyrene-based thermoplastic resins, or those based on them, have high rigidity, but tear strength is much lower than that of simply thick non-foamed sheets or films, so they are easy to tear and cannot be used easily. When removing the seal, the seal material can be easily torn and removed. Therefore, unlike conventional sealing materials made only of non-foamed sheets or films, there is no need to form a tearing auxiliary part such as a knob protrusion for tearing and removing the sealing material, which saves processing time and processing. This will greatly reduce costs.

In addition, in the case of a sealing material made of a foamed sheet or film, once it is heated to cover the cap with shrinkage, the bubbles in the foamed sheet or film themselves will shrink, so even if it is reheated, the sealing material will expand and recover. There's nothing to do. Therefore, like conventional sealing materials made of non-foamed polyethylene film, etc., which have been reheated and removed from the cap,
It is impossible to re-seal the cap by shrink-covering it again, and it is easy to determine whether the cap has been opened or not, and the sealing prevention effect can be fully demonstrated, ensuring the safety and health of the stored items. will be able to accomplish this more reliably.

Furthermore, in addition to the above-mentioned sealing effect, sealing materials made of foam sheets or films also have a cushioning effect during transportation and storage of bottles, etc., and are extremely effective in preventing damage and scratches on the cap part. It can exhibit excellent practical effects.

[Brief explanation of the drawing]

The figure shows an example of this invention.
The figure is a perspective view, Figure 2 is an enlarged sectional view of the main part, Figures 3~
FIG. 6 is a perspective view showing the sequential processing steps. 1... Bottle, 10... Neck, 2... Cap, 3
...Sealing material, 4...Heating plate.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A shrinkable foam sheet or film made of polystyrene-based thermoplastic resin, or a sealing material based on this and heat-shrinked so that it cannot be re-covered after removal, A sealing structure for a cap, characterized in that the cap and the neck of the container body at the bottom of the cap are covered and sealed. 2 The sealing material is heated with hot air at 130℃ for 15 seconds,
The sealing structure of the cap according to claim 1 of the above-mentioned utility model registration, which is made of a polystyrene thermoplastic resin that is heat-shrinkable by 18% or more in the extrusion direction and the direction perpendicular to the extrusion direction.