JPH0242731B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, the outer shell of the container is made of paperboard or the like having relatively high rigidity, and an inner bottom plate or an inner bag having flexibility or elasticity is attached inside the container, and In a paper container in which an outer bottom plate is separately attached to the bottom of the outer shell, a non-bonded part that communicates with the outside air is formed at the bonded part between the container body and the bottom plate that constitute the outer shell. It relates to paper containers.

As is well known, it is generally necessary to sterilize beverage liquids before filling them into containers, and this treatment is usually applied to the inner walls of the containers as well. However, the simplest sterilization method is to treat the liquid at high temperature (approximately 93°C), then fill the container with the liquid at high temperature and then seal it, thereby sterilizing the liquid and the inner wall of the container at the same time. It's a method.
This method is abbreviated as "hot filling" in this specification, but when this hot filling is carried out, the following problems arise. In other words, after hot filling, applying a lid and sealing it, and then cooling it, the volume of the liquid in the container shrinks,
The volume of the contents decreases due to the solidification of the vapor in the container, the volumetric contraction of the enclosed air, etc., and a so-called reduced pressure state occurs. If the container itself is made of a highly rigid material, such as a steel can, it can withstand the reduced pressure inside the can, but if the container is made of plastic or paperboard laminated with plastic, which has relatively low rigidity, There was a problem in that the container dented as the pressure was reduced, making it extremely unsightly. Conventionally, attempts to solve this problem have been made by applying thin Al foil that is relatively easily deformed or Al foil with annular folds to the top part (lid part) of the container, and making this part dent as the volume shrinks. Alternatively, as shown in Japanese Unexamined Patent Publication No. 56-23461, the wall of the container is made of a double material, for example, paperboard and polyethylene, and a part of the wall is made of a non-adhesive part and most of the remaining part is glued. However, there is a known case in which only the inner polyethylene in the non-bonded part is dented inward when the pressure is reduced. However, in the former method, the top portion is significantly recessed, so when attempting to provide easy opening to this portion, it is inconveniently limited. In addition, the top part was thin, so there was concern about impact or dropping, and the impact resistance was also unsatisfactory.

In addition, the latter method may cause problems with gas barrier properties, and the inner recesses may be uneven, making the container look incomplete when viewed from the inside.
I felt a sense of dissatisfaction.

Here, the present invention provides that the container itself is composed of an outer shell made of relatively rigid paperboard (including one laminated with plastic film) and a flexible inner bottom plate or inner bag housed within the outer shell. In other words, the deformation of the container due to the volumetric contraction is absorbed exclusively by the change in the shape of the inner bag, and the The necessary air circulation is carried out through the non-adhesive part actively formed on the outer shell bottom plate, while the strength of the outer shell bottom plate is
It is adapted to be supported by an adhesive section provided between the non-adhesive sections.

To explain the present invention in detail with reference to the illustrated embodiments, FIG. 1 shows a double bottom container having an inner bottom plate, and FIG. This shows the case where the bag is incorporated. In either case, the body 1a of the outer shell 1 is formed into a cylindrical or conical shape, for example, using paperboard with a thickness of approximately 300 to 500μ, and a flexible As shown in FIG. 1, the inner bottom plate 6 is made of a flexible material such as soft polyethylene film, water-resistant paper with a thickness of about 100 μm, or aluminum foil laminated with polyethylene film. Glue it on the inside downwards, or
Alternatively, as shown in FIG. 2, the upper edge 2a of the inner bag 2 made of the above material is adhered to the upper edge of the body 1a. On the other hand, at the lower end of the body 1a,
As an example, the periphery of the bottom plate 3 is bonded through the seaming portion 1b, and in this case, as shown in FIGS. The part is 4 and the non-adhesive part 4a. In such a case, attach the non-adhesive part 4 to the bottom plate part of the outer shell 1.
An air flow path shown by an arrow in the figure is formed through a.

In the present invention, as described above, when bonding the body portion 1a constituting the outer shell and the bottom plate 3, a non-bonded portion 4a is intentionally formed. After temporarily sealing the bottom of the outer shell 1, the interior of the container is filled with the contents by the so-called hot filling. That is, after filling the container with a liquid such as high-temperature juice or alcoholic beverage heated to 60°C to 95°C, the lid 5 is placed on the top of the container to seal it, and then the container is allowed to cool naturally or sprinkled with shower water. Perform forced cooling using methods such as At this time, the liquid in the container, the air layer above it, and the upper liquid vapor layer gradually condense or shrink in volume as they cool, causing the inner bottom plate 6 or the inner bag 2 and the outer shell 1 to The space in between becomes depressurized. In such a case, as shown by the arrow in the figure, the outside air flows between the outer shell 1 and the inner bottom plate 6 or the inner bag 2 through the non-adhesive portion 4a formed by the temporary seal. The outer shell 1 can be deformed solely by the flexibility of the inner bottom plate 6 or the inner bag 2 without being dented. In this case, the inner bottom plate 6 or the inner bag 2
As shown in the figure, the container is completely housed within the outer shell 1, so even if the shape is distorted, the appearance of the container will not be impaired.

After the liquid in the container is cooled, the non-bonded portion 4a may be heated under pressure to perform heat sealing.

The outer shell 1 of the present invention is made of paperboard laminated with synthetic paper or thermoplastic plastic film.

Proceeding to specifically explain an example of the device used when sealing the bottom plate 3 of the outer shell 1 as described above, as shown clearly in FIGS. 4 to 6,
A bonding mechanism 12 is firmly installed in the center of the base 11, penetrating through the base and movable up and down, and a mechanism is provided on the top surface of the base so as to be movable in the radial direction around the axis of the bonding mechanism. A pressurizing bar 13 is provided. The adhesion mechanism 12 includes a vertical rod 15 having a guide member 14 with a dish-shaped cross section, a push-up rod 16 in the shape of a mantle provided so as to surround the vertical rod 15, and a push-up rod 16 that is provided to surround this vertical rod 15, and a push-up rod 16 that is connected to the push-up rod and the above-mentioned dish shape. It consists of an expandable and retractable pressing piece 17 provided between the guide member 14, and these act as follows to seal the bottom plate of the container. That is, the molded container C is placed on the ring-shaped container placement surface 11a at the center of the base 11, and then the vertical rod 15 is moved to the position shown in FIG.
and the pusher rod 16 are moved upward, and at the same time the pressure bar 13 is also moved in the radial direction. In such a case, as is clear from FIG. 6, the plurality of radially arranged pressing pieces 17 are pushed up from below via the push-up rod 16, but in this case, the The sliding surface 17a is guided by the tapered surface 14a of the guide member 14 waiting above the sliding surface 17a, and expands in the radial direction against the elasticity of the spring 17b attached to each pressing piece 17. Pressing piece 17
Since the pressure part 17c is provided on the outer periphery of the
This pressurizing part pressurizes the bottom plate part of the container from the inside toward the outside, while a pressurizing bar 1 disposed on the outside thereof
3 presses the bottom plate portion inward in synchronization with the pressing piece 17. Since the bottom plate of the container is thus subjected to pressure from both the inside and outside, if a pressure-sensitive adhesive has been applied to the bottom plate, for example, the bottom plate will be instantly bonded as a result of the pressurizing operation. If the bottom plate is coated with a heat-sensitive adhesive or laminated with a thermofusible plastic film, etc., an electric heater is installed in advance in the pressing part 17c of the pressing piece 17 constituting the adhesive mechanism 12. is built in, and when the pressing piece presses the bottom plate part, it is heated at the same time to perform thermal bonding. As described above, the bottom plate of the container is sealed by pressure-sensitive adhesive or heat-sensitive adhesive.
7 and the pressure bar 13 are divided in the radial direction as shown in the figure, and as a result, the bottom plate portion of the container is locally bonded along the circumferential direction, forming a so-called non-bonded portion 4a. be.

By the way, after filling the container with the contents,
To carry out the main sealing after cooling, the non-bonded portion 4a may be pressurized or pressurized and heated in the same manner as described above.

FIGS. 7 and 8 show another example of the adhesive mechanism, in which gear-shaped unevenness 18a is formed on the periphery of the pressing piece 18 divided in the radial direction, and the process is performed using only the protruding portion. Pressure may also be applied. In the figure, reference numeral 18b is a heater, and 19 is a receiving member.

9 and 10 show another embodiment of the container bottom plate according to the present invention, which differs from the previous embodiment in the aspect of the temporary seal. That is, the bottom edge of the body 9 in the outer shell 1 of the container is not provided with a seaming part as shown in FIGS. 7 and temporarily sealed it. The adhesive portions 8 and non-adhesive portions 8a constituting the temporary seal portion are arranged in a staggered manner in the lateral direction, as clearly shown in FIG.

When performing temporary sealing as shown in FIGS. 9 and 10, it is preferable to use a pressing piece 20 having a structure as shown in FIG. 11. That is, on the outer periphery of each of the pressing pieces 20 divided in the radial direction, convex portions 20c are formed alternately in the upper and lower halves thereof, thereby creating the shape shown in FIGS. 9 and 10. Staggered adhesive portions 8 are provided. The structure of the bonding mechanism 12 shown in FIG. 11 is the same as that described with reference to FIGS. 4 to 6, except for the outer peripheral portion of the pressing piece 20.

FIG. 12 shows another embodiment of a double-bottomed container having an inner bottom plate, in which the peripheral edge 7b of the inner bottom plate 7 is wound inside the seamed part 1b of the outer shell body 1a and fixed with adhesive. Give an example. Even in this case, the bottom plate 3 of the outer shell 1 is locally sealed to the lower end of the body 1a.

As explained above in detail, the present invention utilizes the non-adhesive portion to hold the bottom plate portion of the paper container until the liquid inside cools down when hot filling the inside of the sealed paper container with liquid. By temporarily circulating air, the deformation of the container during depressurization that occurs during cooling does not affect the outer shell at all, so the appearance of the container can be slightly modified even during hot filling. It is also possible to avoid any damage. Furthermore, according to the present invention, there is no need to consider deformation of the container itself as described above, so materials with high gas barrier properties, such as laminated aluminum foil, can be freely used as the material for the container. It is advantageous.

In the present invention, the air circulation required when the inner container is deformed does not affect the external appearance of the outer container; in other words, it does not affect the outer appearance of the outer container. It exhibits excellent effects because it is realized in an intact state. especially,
Unlike the conventional technology, there is no need to make ventilation holes in the body or bottom plate that make up the outer shell of the container, but instead the outside air is introduced into the adhesive area between the container body and the bottom plate, so the appearance of the container is not spoiled. do not have. Therefore, it is useful when applied to this type of beverage container in that it does not reduce the commercial value and does not make the virginity of the product difficult.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a double-bottomed container in a locally sealed state according to the present invention, FIG.
The figure is a cross-sectional view taken along the - line in Figure 2, 4th to 5th.
The figure is a longitudinal cross-sectional view showing the adhesive mechanism used in carrying out the present invention, FIG. 6 is a cross-sectional view of the main parts of the same, FIG. 7 is a vertical cross-sectional view of another adhesive mechanism of the same, and FIG. FIG. 9 is a plan view showing the action of the piece, FIG. 9 is a vertical cross-sectional view of the bottom plate showing another container temporarily sealed according to the present invention, FIG. 10 is a cross-sectional view taken along the - line in FIG. 9, and FIG. 11 12 is a longitudinal sectional view showing another embodiment of the adhesive mechanism, and FIG. 12 is a longitudinal sectional view showing another embodiment of the double-bottomed container according to the present invention. 1: Outer shell, 1a: Body part, 1b: Sealing part, 2: Inner bag, 2a: Upper edge part, 3, 7: Bottom plate, 4, 8: Adhesive part, 4a, 8a: Non-adhesive part, 5: Lid, 6, 7: Inner bottom plate, 9: Body, 11: Base, 11a: Container placement surface, 12: Adhesive mechanism, 13: Pressure bar, 14: Guide member, 14a: Tapered surface, 15: Vertical Rod, 16:
Pushing rod, 17: Pushing piece, 17a: Sliding surface, 17
b: Spring, 17c: Pressure part, 18, 20:
Pressing piece, 18a: unevenness, 18b: heater, 19:
Receiving member, 20c: convex portion.

Claims (1)

[Claims] 1 A material mainly made of paper, which has relatively high rigidity.
In a container in which a container outer shell is formed of a body, a lid, and a bottom plate, and an inner bottom plate or inner bag made of a flexible material is combined inside the container shell, the periphery of the bottom plate forming the container outer shell and the body are combined. A product made of hot-filled paper, characterized in that the area where the periphery of each part overlaps with the other is used as the adhesive part, and the entire area is not bonded, but a non-adhesive part that communicates with the outside air is formed in a part of the area. container.