JPH0212803B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an easy-open sealing method. The method for sealing the lid to the container is as follows. That is, the container is placed on a seal pedestal that can completely support the entire circumference of the container flange, the lid is placed so as to cover the container flange, and a seal bar heated to a predetermined temperature is applied to the container under a predetermined pressure and time. Press with to complete the seal. The seal pedestal is usually made of metal and supports the entire lower surface of the flange of the container in full surface contact. To open a container that has been hermetically sealed as described above, in the case of a round container, as shown in Figure 1, a lid B is sealed on the container body A, and when opening this, grasp the tab C. Open the lid while pulling it in one direction of the arrow to peel off the sealant of the lid B from the flange of the container body A. However, in the above-mentioned opening method, as shown in Figure 2, the peeling width Y of the sticker changes depending on the location, and the peeling width Y is at its maximum at the beginning of opening, so the peeling strength is also maximum. It often happens that even adults get into trouble and use too much force, losing control of their hands and spilling the contents. In addition, in FIG. 2, X indicates the peeling distance in the opening direction. In order to avoid such a situation, the overall sealing strength is often set low, but this reduces the resistance to external forces and rapidly increases the risk of bag breakage. By the way, the flange width is 5mm for a round container with a diameter of 61φ.
The relationship between the peeling width Y and the peeling distance X for a container of m/m is as shown in the third diagram. As you can see, the peeling distance is 5m/
The peeling width increases up to m, making initial opening difficult. As a result of research in order to eliminate the above-mentioned drawbacks, the present inventor removed the surface layer of the support surface area that supports the part where the peeling width from the container flange is large, which is close to the handle of the lid of the seal pedestal, By embedding a heat-resistant rubber-like elastic material in the removed portion and heat-sealing it using the seal pedestal with heat-resistant rubber-like elastic material formed as described above, the peel strength of the sealed portion where the peel width becomes larger can be improved. The inventors have discovered that the initial opening can be made easier by locally lowering the temperature, and the present invention has been completed based on this knowledge. That is, the gist of the present invention is to use a metal seal pedestal having a support surface that supports the container flange around the entire circumference, support the container body with this seal pedestal, and then attach a lid body having a sealant layer on the lower surface. Place it on top of the container body so as to cover the container flange,
In the heat sealing method of applying heat and pressure with the seal cover, the surface layer of the support surface area of the seal pedestal that supports the part near the handle of the lid body where the peeling width from the container flange becomes large is removed, and the removed part is This easy-open sealing method is characterized by embedding a heat-resistant rubber-like elastic body and heat-sealing using the heat-resistant rubber-like elastic body seal pedestal formed as described above. Hereinafter, the present invention will be explained in detail with reference to the drawings. 4 and 5 show a seal pedestal used in the method of the present invention, FIG. 4 is a plan view, and FIG. 5 is a sectional view taken along the line A-A shown in FIG. The seal pedestal 1 used in the method of the present invention has a space 2 that can accommodate the body of the container to be hermetically sealed and is made of metal such as aluminum, and a support surface 3 that supports the container flange over its entire circumference. Then, the surface layer portion 4 of the support surface region that supports the flange portion where the peeling width from the container flange is large, which is close to the handle of the lid of the container, is removed, and a heat-resistant rubber-like elastic material 5 is embedded in the removed portion. This is what happens. The body portion 7 of the container body 6 is inserted into the space 2 of the seal holder 1 as described above, the container flange 8 is supported by the support surface 3, and then the lid 9 having a sealant layer on the lower surface is attached to its handle 10. The arrangement is adjusted and placed so that the portion 11 closest to the heat-resistant rubber-like elastic body 5 is located on the heat-resistant rubber-like elastic body 5, and the seal bar 12 heats and presses the body. By the heat sealing method mentioned above,
It is possible to heat-seal with a locally low peel strength between the part of the container flange near the handle of the lid where the peel width is large and the area of the container flange surface facing it, thereby making initial opening easier. be able to. In the above method of the present invention, the heat-resistant rubber-like elastic body includes silicone rubber, fluoride rubber, chloroprene rubber, polysulfide rubber, acrylic rubber,
Urethane rubber, isoprene rubber, polybutadiene rubber, ethylene propylene rubber, and the above-mentioned rubbers filled with inorganic substances can be used. Next, examples of the present invention will be given, and regarding the present invention,
I will explain in detail. Example: A conventional seal pedestal made of aluminum with a thickness of 30m/m with a space of 62φ, and a part along the circumference of the conventional seal pedestal (an area that can sufficiently cover the flange) with a thickness of 3m. An improved seal pedestal was formed by removing aluminum over an area of 1.2 m and attaching silicone rubber (hardness 60°) that matched the shape of the removed portion. Polyester film (thickness
12μ)/polyethylene extrusion coat layer (thickness
A laminated film with a sealant layer (thickness 30μ) made of a blend polymer of 20μ)/polypropylene (50% by weight) and high-density polyethylene (50% by weight) was used, while the container body had an outer diameter of 61φ under the flange. A polypropylene cup with a flange width of 5 m/m was used. A ring-shaped blade type aluminum seal bar with a width of 1.5 m/m was used as the seal bar.
Sealing was performed with the conventional and improved seal pedestals. The sealing conditions were a sealing blade temperature of 200°C, a sealing pressure (25φ cylinder pressure) of 2.5Kg/ ^cm2, and a sealing time of 1.0 seconds. After sealing, the container body and lid material were fixed to a tensile tester, and the peel strength was measured at a peel angle of 90° and a tensile speed of 5 m/m/min. The measurement points were positions a, b, c, and d shown in Figures 7 and 8. The results obtained as described above were as follows.

[Table] When sealed with a conventional seal pedestal, the peel strength at each position a to d is 1750 to 1850 g/15
m/m, but when sealed with an improved seal holder, the peel strength at position a, where the silicone rubber is pasted, is 1400g/15m/
Peel strength at m and other b, c, and d positions
Approximately 400g/15 compared to 1750~1850g/15m/m
It was as low as m/m. Next, the lid material was actually punched out using a die with a handle attached as shown in FIG. Then seal the handle with a of the pedestal.
Seal was performed under the above-mentioned sealing conditions in synchronization with the position, and 10 people peeled it off by hand and observed the initial opening properties according to the parameters. As shown in Table 2, the results are as follows:
All of them judged the improved version to be easier to open.

[Table] As detailed above, according to the method of the present invention, it is possible to locally lower the peel strength of the seal portion where the peel width becomes large, thereby making it possible to improve the initial unsealability.

[Brief explanation of drawings]

Figure 1 is a perspective view showing the unsealing situation of a conventional sealed container with a handle, Figure 2 is a plan view showing the peeling width and peeling distance at the container flange, and Figure 3 is a graph showing the change curve of peeling distance versus peeling width. , Figures 4 and 5
The figures show an improved seal pedestal used in the method of the present invention, FIG. 4 is a plan view, FIG. 5 is a sectional view taken along the line A-A shown in FIG. 7 and 8 are cross-sectional views showing the state in which
The figure shows four locations a, b, and
FIG. 9 is a plan view showing c and d, and FIG. 9 is a plan view of the lid used in the example. DESCRIPTION OF SYMBOLS 1...Seal pedestal, 2...Middle part, 3...Supporting surface, 5...Heat-resistant rubber-like elastic body.

Claims (1)

[Claims] 1. Using a metal seal pedestal with a support surface that supports the entire circumference of the container flange, the container body is supported by this seal pedestal, and then a lid body having a sealant layer on the lower surface is placed to cover the container flange. In a heat sealing method in which the seal is placed on a container body and heated and pressurized with a seal bar, a support surface area of the seal pedestal that supports a portion where the peeling width from the container flange becomes larger is close to the handle of the lid. An easy-to-open package characterized in that the surface layer portion of the product is removed, a heat-resistant rubber-like elastic material is buried in the removed portion, and heat-sealed using the heat-resistant rubber-like elastic material seal pedestal formed as described above. Seal method.