JPS5940616B2 - Manufacturing method for paper containers with bottoms - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a paper container with a bottom for the purpose of manufacturing a cylindrical airtight container with a bottom from paper material.

Conventionally, various methods for manufacturing cylindrical paper containers have been proposed and each has been put to practical use, but the present invention proposes a new method for manufacturing an airtight container that is cylindrical as a whole.

Conventional methods for manufacturing paper containers include folding square paper along the folds to form a square cylinder and fixing a bottom plate to the bottom of the square paper, and rolling the square paper into a cylinder and pasting the edges to form a cylinder. After forming the wall, a method is known in which a bottom plate is fixed to the lower part of the wall, or a method in which a tape-like paper material is spirally wound around the outer wall of a cylindrical core type, the overlapping part is pasted, and a bottom plate is fixed to the lower part of the wall. . However, in each of the above methods, the side wall and bottom plate of the container are manufactured independently and then fitted and fixed together, so the relationship between the side wall and the bottom plate is maintained solely by adhesive force. In addition, it not only required a complicated process to supply two independent materials and airtightly fix them in a predetermined position, but also required special consideration in terms of strength. There is also a known technology (Utility Model Publication No. 31-13077) in which the bottom plate and side walls are integrally molded by folding them together, but when a cylindrical container is formed using this technology, the edges of the sheets overlap extremely. This results in a significant difference in sidewall thickness between the bottom and mouth of the container.

In other words, although such a technique can be used for a container having a tapered wall with a large diameter mouth, it is not suitable for a cylindrical container.

The method of the present invention is to apply a predetermined number of sheets (
While holding the bottom plate made of material in which short fence pieces for side walls (usually number to ten pieces) are arranged radially at equal intervals, bend the peripheral edges of each of the short fence pieces and the bottom plate at almost right angles, and then The overlapping portions of the short fence pieces are adhered to each other to form a side wall, and then reinforcing paper is applied to the side wall surface to produce a paper container with a bottom.

Since this invention uses a material in which short fence pieces for the side walls are provided radially around the periphery of the bottom plate, the strength of the connection between the side wall and the bottom plate is determined by the strength of the material and the area of the connection portion without any consideration. The above-mentioned problems of the prior art have been solved so that it has predictable strength and can be easily molded into a desired shape using a core mold and an outer mold.

That is, this invention will be explained based on examples.

A material is used in which short fence pieces 2, 2 for side walls are provided radially on the outer peripheral edge of a circular bottom plate 1 made of a strong paper material. The short fence pieces 2, 2 are provided at equal intervals and close to each other, and cutouts 3, 3 are provided near the bottom plate so that they are overlapped over the entire length from near the bottom plate when forming into a tube. . The bottom part of the cylindrical core mold 4 is stacked on top of the bottom plate 1 and stands upright, and then the cylindrical core mold 4 is lowered into the outer mold 5 (or the outer mold 5 is raised) and the bottom plate 1 is placed around the cylindrical core mold 4. and the short fence pieces 2, 2, and the overlapping parts of each short fence piece are pasted.

This adhesive may be an adhesive or a heat-sealable synthetic resin film (for example, polyethylene film), and various conventionally known adhesives (natural or synthetic adhesives) may be used as the adhesive. Can be done. Once the bottomed cylindrical body is produced as described above, the exterior paper 6 is attached to the entire outer peripheral wall, or the interior paper 7 and the exterior paper 6 are attached to complete the container of the present invention.

As for the material used in this invention, short fence pieces 2, 2 are provided on the outer peripheral edge of the bottom plate 1, and the number of short fence pieces 2, 2 is limited to the bottom plate 1.
It varies depending on the diameter or material of the cylindrical container, or the shape of the cylindrical container to be manufactured (for example, cylindrical, square cylindrical, or polygonal cylindrical). Further, the adhesive is applied to the adhesive portion of each short piece, or is layered over the entire surface, and is appropriately selected depending on the properties of the adhesive. For example, when laminating a polyethylene film, the paper material of the present invention can be obtained by coating the entire surface of a paper material and punching out this paper material. The adhesive may be applied by a conventionally known method using a coating roller, by brush coating, by spraying, or by other means that match the properties of the adhesive. Although a cylindrical container was produced in the above embodiment, a square or polygonal cylindrical shape can also be produced in the same manner, and
The side wall can also be shaped like a funnel, widening towards the opening.

There is no particular limitation on the adhesive allowance for each short fence piece, as long as the adhesive portion has sufficient strength.

As for the number, several to ten pieces would be practically preferable. Next, the reinforcing paper also serves as the exterior paper, and can be freely applied with various types of printing, reinforcing the entire product and increasing its commercial value in terms of design. In many cases, the interior paper is not necessary for strength reasons, but it may be advantageous to cover the interior with an interior paper in terms of the appearance, and the adhesive can be prevented from being exposed by the interior. That is, according to this invention, since the side walls are formed by short fence pieces connected to the periphery of the bottom plate, there is an effect that the connection strength between the bottom plate and the side walls can be estimated in advance based on the connection area of both materials.

Furthermore, since the material can be punched and formed, it can be formed into the same shape with high precision, which has the effect of improving the homogeneity and precision of the product. In addition, since the side wall can be formed by simply fitting the core mold and the outer mold into each other, the manufacturing process and equipment are simple and easy, and high-speed processing is possible, making mass production possible.

[Brief explanation of the drawing]

Fig. 1 is a developed plan view of the material used in this invention in the case of 8 short fence pieces, Fig. 2 is a developed plan view of the case of 10 short fence pieces, and Fig. 3 is a front view of the same material in the middle of processing. Fig. 4 is a plan view of the product, Fig. 5 is a longitudinal sectional front view, Fig. 6 is a longitudinal sectional front view of the product of the present invention when used as a covered can, and Fig. 7 is a longitudinal sectional front view of the product as well. FIG. 3 is a partially cutaway front view of the device in use. 1...Bottom plate, 2...Short fence piece, 3...
...Depth of cut, 4...Cylindrical core type, 5...
・Outer mold, 6... Exterior paper, 7... Inner paper.

Claims (1)

[Scope of Claims] 1. While holding a bottom plate made of a material in which a predetermined number of side wall short fence pieces are provided radially and at equal intervals around the entire circumference of the bottom plate, the peripheral edge of each of the short fence pieces and the bottom plate is held in place. A paper container with a bottom, characterized in that the side wall is formed by bending the paper container at almost right angles, and then pasting the overlapping parts of each adjacent short fence piece to each other to form a side wall, after which a reinforcing plate is attached to the side wall surface. Manufacturing method. 2. The method for manufacturing a paper container with a bottom according to claim 1, wherein the reinforcing paper is used as an exterior paper or both an interior paper and an exterior paper. 3. The method for manufacturing a paper container with a bottom according to claim 1, characterized in that an adhesive layer is provided on the entire surface or adhesive side of the short fence piece. 4. The method for producing a paper container with a bottom according to claim 3, wherein the adhesive layer is an adhesive that produces adhesive properties by pressure and heating, or a heat-fusible synthetic resin layer.