JPH0413228B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a package in which a self-supporting bag is filled with contents, which has a good ability to protect the contents, has a large sealing strength, and does not break during heat sterilization. be.

Conventionally, flat bags have been used as packaging bodies, but since they are flat bags, they are not self-supporting and have no display effect, and for ease of handling, a folded part is formed in a tube-shaped film at the bottom. A gusset bag is known as a bag that stands on its own when a seal is provided and the contents are filled, but in the upper part of the gusset bag, four films are polymerized in the folded part, and two films are polymerized in other parts. Therefore, if this is sealed in a line with a predetermined width, there will be a portion where the thickness of the overlapped layer is four and two layers, resulting in a step difference. In addition, it is difficult to completely thermally bond the stepped portion, and a small space remains in the stepped portion, resulting in poor adhesion or weakening of the thermal bonding strength.Especially when heat sterilization is performed, the contents may be damaged. Due to the pressure applied, the bag may break and the contents may leak out from the step formed between the four film overlapped areas at the end of the folded part and the other two film overlap areas, or the contents may come into contact with air. If the contents are bitten and the opening is heat-bonded and heat sterilized, the contents that protrude from the heat-bonded area may solidify, or the contents may remain on the top, making it unsanitary and causing damage to the package. There were drawbacks such as the possibility of spoiling the aesthetic appearance of the product.
Furthermore, if the contents are particularly prone to foaming, if the contents are bubbled immediately after filling, the contents are bitten and thermally bonded to remove the bubbles from the packaging bag, otherwise the protruding contents may come into contact with the air. This results in discoloration or chemical changes in the contents, which impairs the aesthetic appearance and is unsanitary.

The present invention provides a package free of such drawbacks, and will be described below with reference to embodiments shown in the drawings.

Heat-adhesive synthetic resin film 1 such as polyethylene, polypropylene, polyvinyl chloride, etc. on the inner surface, and aluminum foil, polyester, etc. on the outer surface as necessary.
A packaging material 3 formed by laminating one or more layers of a protective layer 2 made of nylon, polypropylene, etc., which is strong, has excellent heat resistance, airtightness, etc., is shaped into a cylinder, and a folded part 4 is formed inside along the longitudinal direction. , an upper opening 6 of a gusset bag formed by thermally bonding a bottom film 5.
It fills the contents even more.

After the contents are filled almost completely, the contents are bitten and thermally bonded below the upper edge, and a space is formed above the thermally bonded portion, the upper edge is thermally bonded, and two-step thermal bonding is performed. It is a sealed package.

Furthermore, since the above-mentioned folded part 4 is folded in, a total of four layers are overlapped, and in the other part, that is, the center part, two layers are overlapped, and a stepped part is formed between the fourth layer and the second layer. be done. When the stepped portion is thermally bonded in a straight line, a small space is created in the stepped portion. This space causes poor thermal adhesion and causes the bag to break due to the stepped portion. In the case where such a stepped portion is formed, the present invention further heat-bonds four portions of the stepped portion, that is, the end portion 4' of the folded portion 4, to the two-step thermally bonded structure. In this way, the portion where the stepped portion is formed will not cause poor thermal adhesion, and strong adhesion can be achieved.

In the package of the present invention, contents are filled in a gazette bag, the contents are bitten and thermally bonded below the upper edge, and a space is further formed above the thermally bonded portion and the upper edge is thermally bonded. , which completely seals only the contents. Then, if necessary, only the step part of the gusset bag is heat-bonded again. During heat sterilization such as retort sterilization and boil sterilization, the contents leak from the poorly bonded part or weakly heat-bonded part due to heating during heat sterilization. There's nothing to do. Furthermore, even if the contents leak from the weakly heat-bonded part, the contents remain in the space because a space is formed above the heat-bonded part, and no pressure is applied to the heat-bonded part at the upper end. Therefore, the upper end thermally bonded portion will not be torn, and the contents will be completely protected and the heat-sterilized contents will not change in quality. Therefore, it can be stored for a long period of time, and since the contents are entrapped and thermally bonded, the contents do not come into contact with air and do not oxidize, making it highly suitable for protecting the contents. It is something.

Furthermore, according to the present invention, since the upper and lower layers are thermally bonded, the seal is perfect even when filled with solid-liquid mixed contents, and even when filled with foamy contents. Since the material is bitten and thermally bonded, the contents do not come into contact with air, so there is no risk of foaming. Moreover, the appearance of the package is beautiful and hygienic.

Furthermore, the packaging body of the present invention is self-supporting and has good handling properties, and the opening for filling the contents of the gazette bag is thermally bonded in two stages, upper and lower, and the stepped portion of the thermally bonded portion is Because the bag is double heat-bonded, the heat-bonded part will not break even when the contents are pressurized during heat sterilization.In particular, the heat-bonded part on the top edge has a heat-bonded part on the bottom as well. The air-containing part at the top of the bag does not mix with and have no influence on the contents filled at the bottom of the bag, so the wall materials on both sides (film sheet material 3) remain flat. Strong thermal bonding strength can be obtained without any deformation. Furthermore, in the case of contents that are particularly prone to foaming, the filling speed is fast because the contents can be bitten and thermally bonded without having to wait until the foam disappears.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the gusset bag before it is filled with contents, and FIG. 2 is a perspective view of the gusset bag after it is filled with contents. 1... Heat-adhesive synthetic resin film, 2... Protective layer,
3... Packaging material, 4... End of folded part, 5... Bottom film, 6... Upper opening.

Claims (1)

[Claims] 1 A folded part 4 is formed inside along the longitudinal direction of a cylindrical body having a heat-adhesive synthetic resin film 1 on the inner surface.
In the self-supporting bag, which is formed with a bottom heat-bonded part at the bottom end, the contents are filled through the upper opening, and the contents are bitten and heat-bonded at an appropriate position below the top edge. A space is formed in the upper part of the heat-bonded part, the upper edge is heat-bonded, and four parts of the end 4' of the folded part 4 heat-bonded to the two stages are sealed by heat-bonding 7. A packaging body characterized by: