JPH07108703B2 - Liquid filling and sealing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for filling a packaging bag having a heat-adhesive resin layer on its inner surface with a liquid, particularly a foamable liquid.

[Conventional technology and its problems]

Conventionally, when a liquid is generally filled in a packaging bag, the liquid is filled so as not to be completely filled in the packaging bag, and an opening is sealed to leave a head space at the top of the packaging bag. In the case of filling a foaming liquid such as soy milk, a method has been adopted in which the liquid is allowed to overflow from the packaging bag, the foam is removed, and the opening is sealed. However, when the head space is provided for sealing, the air remaining in the head space may deteriorate the contents. Also, when liquid is overflowed and filled, the outer surface of the packaging bag is dirty or the liquid adheres to the inner surface, so heat sealing is not performed sufficiently, and heat sealing bar (seal bar) at the time of sealing. As a result, the contents adhering to the outer surface of the packaging bag may be burnt and give off an offensive odor, or the main body of the filling machine and the working environment may be contaminated.

[Problems to be solved by the invention]

The present invention has been made in view of the above circumstances, in filling the packaging bag with the liquid, after the liquid is allowed to flow into the packaging bag, the air present in the upper portion of the packaging bag so as not to overflow the filled liquid. After discharging, the contents are bitten slightly below the upper end of the opening of the packaging bag and heat-bonded (so-called,
It has been found that the above-mentioned problems can be solved if the upper part of the packaging bag is sealed after the upper part of the liquid is sucked out from the heat-bonded portion by suction.

[Means for solving problems]

That is, the present applicants have already filed a patent application for the same purpose.
When filling the packaging bag with liquid as No. 59-117682,
Biting the contents slightly below the upper edge to heat bond,
Furthermore, a method has been proposed in which a space is formed in the upper portion of the heat-bonded portion and the upper edge portion is heat-bonded and hermetically sealed. However,
In this method, when the content is a foaming liquid, the length of the packaging bag is unnecessarily lengthened, the heat adhesive strength when the content is bitten is weak, or the foam packaging is used. It flowed to the outer surface of the bag, leaving an unsolved part of the above problem.

Therefore, as a result of further study, the inventors of the present invention, after injecting the liquid into the packaging bag, bite the contents and heat-bond the remaining liquid to the upper portion of the remaining liquid or foam by using appropriate means. The present invention has been completed by adopting a method of discharging it externally.

An object of the present invention is to provide a filling method that does not leave a so-called head space in which air remains inside a packaging bag when filling a liquid. It is even more effective when the liquid to be filled may deteriorate due to the air remaining in the head space.

If the liquid to be filled is a foamable liquid, the liquid will not overflow, so the outer surface of the packaging bag will be soiled,
The purpose of the present invention is to provide a filling method in which thermal bonding does not become incomplete.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is an example of a packaging bag used in the present invention, which is a composite packaging material using a heat-adhesive film 1 such as polyethylene / polypropylene as the innermost layer. 2 is a surface material laminated on a heat-adhesive film, which is polyethylene.
Plastic film such as polypropylene / polyester / nylon, metal foil such as aluminum foil are selected in order to give desired properties such as heat resistance, air proofness, light shielding property, rigidity, etc. In the case of manufacturing a packaging bag using these packaging materials, the heat-adhesive film may be folded back to the innermost layer or overlapped to form the necessary peripheral side edges. A so-called three-sided bag that is heat-bonded, or a gusseted bag with folds formed on both side edges is formed, or the above-mentioned packaging material is reverse V so that it becomes the bottom of the packaging bag.
This is a so-called self-supporting packaging bag that is inserted in a letter shape.

2 (a) to (e) show that when the liquid is filled in the packaging bag 3 having the heat-adhesive resin layer as the innermost layer as described above, no air remains in the head space after the filling. FIG. 3 is a schematic process diagram showing a filling and sealing method of the present invention for filling a liquid in such a manner that after the liquid 4 is introduced into the packaging bag 3 and filled, either side edge near the packaging bag opening 5 is pulled outward, or The outer wall surface of the packaging bag 3 is pressed to discharge the air remaining on the upper portion of the packaging bag 3, and the liquid is bitten into the lower portion of the upper end of the opening 5 and the liquid submerged seal 6 is used to thermally bond the upper portion of the bonded portion. The liquid in 1 is suction-evacuated using an appropriate means 7, and then the upper end 8 of the packaging bag is heat-bonded, which is particularly useful when applied to a foaming liquid such as coffee drink and soy milk. . In this case, the heat sealing includes a seal that bites the contents, and a heat-bonding seal at the opening, that is, the upper end after discharging the residual liquid at the upper part, a seal by a hot plate, an impulse seal,
Known methods such as ultrasonic sealing and induction heating sealing can be used. Further, as a method of discharging the liquid remaining on the upper portion to the outside, an appropriate means, for example, the nozzle 7 of the portion may be inserted to suck the remaining liquid.

〔The invention's effect〕

As described above, the present invention fills a liquid in a packaging bag having a heat-adhesive resin layer as the innermost layer, and seals the liquid, and then allows the liquid to flow into the packaging bag, and then remains on the upper portion of the packaging bag. Air is discharged, the contents are bitten at the lower end of the opening and heat-bonded, and the liquid above the heat-bonded portion is sucked out and then the opening is heat-sealed. Since there is no head space inside the packaging bag,
There is no fear of altering the contents, and the liquid does not overflow outside during filling, so the outer surface of the packaging bag is not contaminated. Therefore, the filling machine is not polluted and the working environment is not deteriorated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a packaging material used in the present invention, FIG. 2 is an explanatory view showing the outline of the steps of the present invention, (a) a step of filling a liquid, (b) Is a degassing step of pulling both side edges outward, (c) is a step of heat-bonding the lower part of the opening by biting the liquid, and (d) is a subsequent suction and discharge step of the remaining liquid. ) Indicates the heat sealing step of the opening, respectively. 1 ... Thermal adhesive film, 2 ... Laminated film, 3 ... Packaging bag, 4 ... Liquid, 5 ... Opening part, 6 ... Liquid sealing part, 8 ... Upper end part

Claims (1)

[Claims] 1. A packaging bag 3 having a heat-adhesive resin layer as an innermost layer.
When the liquid 4 is filled in and sealed, the liquid 4 is allowed to flow into the packaging bag 3, and then the contents are bitten and heat-bonded 6 at a position slightly lower than the upper end of the opening 5 to form the heat-bonded portion. A method for filling and sealing a liquid, characterized in that the liquid 4 above 6 is sucked out using an appropriate means 7 and the opening 5 is heat-sealed.