JPH0385226A - Filling sealing method for paper container - Google Patents

Abstract

PURPOSE:To prevent defective sealings from happening by a method wherein after a liquid has been filled from the opening of a container, a compressed gas is blown to a sealing part on the inner surface of the opening, and then the opening is heated and sealed by seal bars by heating and pressing. CONSTITUTION:From an opening 2 of a container 1, a liquid is filled, and after a compressed gas has been blown from an air nozzle 10 of which tip is approximately rectangular to a sealing surface at the opening 2, the inner and outer surfaces of the opening 2 are heated by a heater 3 to give a bondable condition. After the opening has been folded into a designated form, the tops of higher edges 5 are heated and pressed to be sealed from both sides by seal bars 4. For the compressed gas to be used, a gas under a germfree condition, which is sterilized through an air filter, is used. Since the compressed gas is blown approximately at right angle to the inner side of the opening of the container, the filled liquid does not splash out. In addition, adhered liquid on the inner surface can be removed instantly, and the following heating can be performed well.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for filling and sealing a paper container filled with a liquid such as milk or juice.

BACKGROUND OF THE INVENTION Paper containers as shown in FIG. 3 are often used as containers for filling liquids such as milk and juice.

This paper container is made of paper-based material with heat-bondable resin layers such as polyethylene on both sides, and is bent from the ruled line to form a bottom shape.When filling this container with liquid, , it was common to carry out the process shown in FIG.

First, as shown in FIG. 4a, liquid is filled from the opening 2 of the container 1, and then, as shown in FIG. do. Then, as shown in FIG.
The step 5 part was sealed.

<Problems to be solved by the invention> However, when filling the container with liquid, the liquid may scatter and adhere to the inner surface of the opening of the container, or the filled liquid may rise due to capillary action and rise to the opening. There was something to do.

If liquid adheres to the inner surface of the opening in this way, when heated with a heater, the part to which the liquid has adhered will not be sufficiently heated.
The resin layer at the opening was not sufficiently melted, and even when heated and pressed using a seal bar in the next step, the seal at the top of the step remained incomplete.

Further, when manufacturing the container, first, when the side wall is bonded to form a cylinder, the bonded portion of the side wall is subjected to a frame treatment using a gas burner or the like to bond and integrate. The heat of this frame treatment oxidizes the surface of the resin layer on the inner surface of the opening, making it difficult to bond. 'If the liquid adheres to the oxidized resin layer as described above, the seal will be incomplete.

Therefore, it is possible to remove the adhering liquid by spraying compressed gas onto the opening, but there is a risk that the liquid will splatter due to the compressed gas being sprayed, resulting in more liquid adhering to the inner surface of the opening. there were.

When reducing the pressure of the compressed gas to solve this splashing phenomenon, the attached liquid was not removed.

In the absence of any suitable improvement measures, conventional filling and sealing methods were used, but the heating temperature, pressure, and shape of the sealing bar were changed during sealing. Even if the sealing process was improved in this way, the incidence of sealing failure was approximately 0.1 to 0.5%.

Therefore, an object of the present invention is to provide a method for filling and sealing paper containers that eliminates the occurrence of sealing defects.

Means for Solving the Problems> The present invention provides a method for filling and sealing a paper container with a bottom shape by bending a material mainly made of paper with heat-bondable resin layers on both sides, and filling and sealing the container with a liquid. This method of filling and sealing a paper container is characterized in that the opening is heated and sealed by heating and pressurizing with a seal bar.

In the present invention, compressed gas is blown almost perpendicularly to the inner surface of the opening of the container, so the filled liquid does not splash out, and the liquid adhering to the inner surface can be instantly removed, ensuring that the next heating is sufficient. You can do it.

<Example> Next, examples of the present invention will be described.

The second paper has a resin layer made of polyethylene on both sides of the paper.
In this method, a material having the shape and ruled lines shown in the figure is bent from the ruled lines, and a container having an opening formed therein is filled with liquid and sealed in the process shown in FIG. 1.

First, as shown in FIG.
After blowing compressed gas from an air nozzle 10 that is substantially perpendicular to the sealing surface, the inner and outer surfaces of the opening 2 are heated by the heater 3 to make them bondable, as shown in FIG.

After folding the opening into a predetermined shape as shown in FIG. 4D, the upper part of the step 5 is sealed by heat-pressing from both sides with a seal bar 4.

Here, the compressed gas used in the present invention is a sterile gas that has been sterilized through an air filter, and the pressure is 0.2 kg/
C1i or higher was used.

Further, the tip of the air nozzle that blows out the compressed gas is brought as close as possible to the inner surface of the opening so that the compressed gas is sprayed intensively onto the sealed portion.

Moreover, the same effect can be obtained by similarly spraying steam instead of compressed gas.

<Effects of the Invention> As described above, the present invention sprays compressed gas on the inner surface of the opening almost perpendicularly to the inner surface of the opening before heating the opening, thereby sealing the opening under the same heating and sealing conditions as before. However, we were able to eliminate the occurrence of sealing defects.

In this way, it has become possible to eliminate sealing failures due to filling liquid, which conventionally would inevitably occur, by blowing compressed air onto the inner surface of the opening, without changing the conventional filling and sealing processes.

[Brief explanation of drawings]

Figures 1 a - d are explanatory diagrams showing the method of the present invention, Figure 2 is an explanatory diagram showing an example of the shape of a paper container to which the method of the present invention is applied, and Figure 3 is an explanatory diagram showing an example of the shape of a paper container to which the method of the present invention is applied. FIG. 4 is an explanatory view showing the opening portion, and is an explanatory view showing a conventional filling and sealing method. Container heater step 2...Opening 4...Seal bar lO...Air nozzle permit Application Hitotoppan Printing Co., Ltd. Representative Kazuo Suzuki (and one other person) Figure 1 LCI Figure 1 (d) Figure 2 Figure 3

Claims (1)

[Claims] (1) In a method in which a paper-based material with heat-bondable resin layers on both sides is folded along the ruled lines, a formed paper container is filled with liquid and sealed, after filling the liquid from the opening of the container. Spray compressed gas on the seal on the inner surface of the opening,
A method for filling and sealing a paper container, characterized in that the opening is then heated and sealed by heating and pressurizing with a seal bar.