JP2894902B2 - Manufacturing method of infusion bag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a plastic infusion bag, and more particularly to an improvement in the mouth of the infusion bag.

[0002]

2. Description of the Related Art As a method for manufacturing an infusion bag, a blow molding method is generally employed in which a parison in a molten state is sandwiched between molds and compressed air is blown into the parison to expand the parison.

[0003]

However, when a bag for infusion is blow-molded, there is a problem in strength in that the mouth becomes thinner, which makes it impossible to hold the mouth in a transport process or the like. Therefore, recently, the amount of extruded molten parison in the part corresponding to the mouth of the container is adjusted as much as possible in comparison with the body part, but the method itself has its own limitations, It was originally difficult to make the mouth thick by blow molding.

[0004] Usually, the molten parison is formed by protruding from the mold and the protruding portion is discarded after molding. Therefore, if the amount of the molten parison pushed out at the mouth of the container is increased, the molten parison is discarded. The amount was extremely large, and there was a problem that almost half of the amount of resin used in one molding was discarded. In particular, in the case of a flat infusion bag, the body portion is extremely wide with respect to the narrow mouth, so that a large amount of resin is required to make the body portion wide, and accordingly, the amount of resin consumed near the mouth is accordingly reduced. The amount was remarkably large, and the amount of waste was extremely large.

An object of the present invention is to provide a method of manufacturing a plastic infusion bag capable of improving the strength of the mouth of a container and reducing the amount of resin waste.

[0006]

In order to achieve the above-mentioned object, the present invention provides a method of forming a cylindrical PE, P,
Attached mouth reinforcement made of P or EVA and melted
A tubular parison made of PE or PP is used as this mouth reinforcement.
After being stretched in, it is sandwiched by a mold and compressed in the parison.
Plastic transportation that blows air and inflates and molds
The liquid bag manufacturing method was adopted. In this method, a tubular reinforcing member made of PE, PP or EVA is attached to the tip of a blow pin in advance, and this reinforcing member is molded together with a cylindrical parison made of PE or PP in a molten state. after sandwiched, such molded by inflation by blowing compressed air into the parison, Paris the mouth reinforcement
It is not a method of integrally molding inside the son, but a mouth reinforcement
This is a method that can be integrally molded outside the parison.

The mouth reinforcement is preferably obtained in advance as an injection-molded product, for example, and is preferably made of a material that can be firmly joined to a parison used in blow molding. When the material of the parison is PE or PP, PE, PP, EVA or the like is preferable.

[0008] If the screw is cut in advance at the mouth reinforcing member at the stage of injection molding, the screwed state with the cap can be ensured.

[0009]

According to the present invention, a tubular reinforcing member made of PE, PP or PVA is attached to the tip of a blow pin in advance, and this reinforcing member is joined with a cylindrical parison made of PE or PP in a molten state. After sandwiching in a mold, the parison is blown and blown into the parison to inflate and mold.Therefore, even if the molten parison in the portion corresponding to the mouth of the container is extruded and the wall is thinned, the mouth is reinforced by the mouth Because it is strengthened by the body, it can be manufactured stably and the mouth can be reliably held in the transporting step or the like. In addition, the amount of the molten parison to be extruded can be reduced, so that the amount of resin to be discarded in one blow molding is significantly reduced. On average, the amount of resin to be discarded is 1/4 or less of the conventional amount of waste. Rich.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS For example, as shown in FIG.
And a mouth reinforcing member 5 made of a cylindrical PE, PP or EVA.
Cylindrical pariso of PE or PP attached and melted
After the extension 3 is extended into the mouth reinforcement 5, it is sandwiched by the mold 4.
And blow compressed air into the parison 3 to inflate it.
Molding.

Also, for example, as shown in FIG.
The mouth made of PE, PP or EVA at the tip of
Attach the original reinforcement body 2 and put the mouth reinforcement body 2 in the molten state
And cylindrical parison 3 made of PE or PP
It is sandwiched by the mold 4. And blow pin in the parison 3
The method of injecting compressed air and inflating from 1 is also adopted.
Can be used.

The present invention is not limited to the above embodiment. The present invention is particularly suitable for a flat infusion bag having a large body portion and a narrow mouth, but is not particularly limited, and can be used as a method for manufacturing an infusion bag of another shape.

FIG. 3 shows an infusion bag 6 manufactured by the method of the present invention.

[0014]

As described above, according to the present invention, the present invention is pre-cylindrical PE, producing a blow molded bag infuse resin made by attaching the mouth reinforcement consisting of PP or EVA PE or PP on the mold edges Because of this method, the mouth of the infusion bag after molding is strengthened, and the amount of resin to be discarded is significantly reduced, which is excellent in economic efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main part of a blow molding machine showing a state in which a mouth reinforcing body is attached to a blow pin.

FIG. 2 is a schematic view of a main part of a blow molding machine showing a state in which a mouth reinforcing body is attached to an edge of a mold.

FIG. 3 is a perspective view showing an example of an infusion bag manufactured by this manufacturing method.

[Explanation of symbols]

 Reference Signs List 1 blow pin 2 mouth reinforcement 3 parison 4 mold 5 mouth reinforcement 6 bag for infusion

Claims (1)

(57) [Claims] 1. A cylindrical PE or P is formed on an inner edge of a mold in advance.
A mouth reinforcement body made of P or EVA is attached, and a cylindrical parison made of molten PE or PP is stretched into this mouth reinforcement body, then sandwiched by a mold, and compressed air is blown into the parison to form the parison. A method for producing a plastic infusion bag, comprising: