JPS6353019B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming and bonding plastic fasteners and plastic adducts into multilayer or single layer films.

In bags made of various films (multi-layer or single-layer films) that have a plastic fastener with an opening/closing function at the opening, a plastic fastener is placed near the plastic fastener to prevent the film from adhering to the end surface of the opening and to act as an opening knob. The opening and closing function of a bag with a fastener can be increased by attaching a bead to facilitate the opening and closing of the bag, or a strip to reinforce the upper part of the bag between the bead and the plastic fastener. be able to.

The present invention relates to the manufacture of a film with additions such as a fastener and a bead or strip before manufacturing the above-mentioned bag body, and the fastener and additions are formed into a flat shape as shown in FIG. film 1
Additions such as the bead 2 and the strip 3, as well as the fasteners of the male claw 4 and female claw 5, are extruded from separate dies and are welded together by the heat retained during formation.

However, in the conventional extrusion bonding method, as shown in FIG.
The additive 7 and the fastener 8 are mutually welded to the film 1 moving on the adhesive roll 9 disposed near the die 6 by the respective heats, and the press roll 1
This was a method in which the film 1 was transferred to the cooling step 11 by pressing the additional material 7 at 0.

According to this conventional method, the additive 7 and the fastener 8, which have different shapes and material weight ratios, are extruded from the same die under the same forming temperature conditions. Various inconveniences were occurring.

That is, as described above, since the fastener and the additive have different shapes and weights, it is necessary to set the forming temperature to suit each. However, when forming using the same die, it is not possible to set individual forming temperatures, and it is necessary to set one of the temperatures for forming.

Therefore, for example, when a die temperature suitable for forming a fastener is set, additive 7 has a lower material specific gravity than fastener 8, has a thinner flat shape, and has a larger heat dissipation area, so it retains its own properties after extrusion. The heat dissipation is greater than that of the fastener 8, and therefore, under the same conditions as the fastener 8, there is a problem in that the film 1 is not mutually welded. Therefore, if the die temperature is set to be suitable for adhering the additive to the film, the temperature is too high for forming the fastener, and the shape of the fastener will melt and break.

In addition, in the conventional method, since both the fastener and the additive are bonded to the film 1 on the same roll 9, the fastener 8 is bonded on the adhesive roll 9 when the additive 7 is pressed by the press roll 10. Under the influence of pressure up to the roll position, the rubber of the roll 9 at that location undergoes elastic deformation, and the location becomes uneven. Therefore, when the fastener 8 is bonded, the uneven deformation of the fastener bonding position on the roll causes the fastener to be bonded at an angle, or the fastener itself to be deformed and bonded.

In other words, since the adhesive roll 9 is constantly pressurized by the press roll 10 for a long period of time, the pressurized area and its surroundings locally deteriorate and undergo plastic deformation, losing its elasticity as a rubber. As mentioned above, the adhesive surface of the roll has an uneven shape, which causes the fastener to adhere at an angle or deform when fixing the fastener 8 to the film 1.

In order to solve the above-mentioned conventional problems, the present invention has the following features:
A molding die dedicated to additives and a molding die dedicated to fasteners are installed separately in one extruder, and the molding temperature of the die dedicated to additives is set to be higher than the molding temperature of the die dedicated to fasteners. The material and the fastener are separately extruded and bonded to each other to a film moving on an adhesive roll.

Embodiments of the present invention will be described below with reference to FIGS. 3 and 4. A first molding die 12 for extruding the appendix 7 into an extruder 18, and a second molding die 13 for extruding the fastener 8 of the male claw 4 and female claw 5.
are installed separately and in parallel. Then, the first molding die 1
The molding temperature of No. 2 is set to be higher than the molding temperature of the second molding die 13. A roll 14 is provided near the first forming die 12 and serves as a joining point between the film 1 loosened and transferred from the winding frame and the additional material 7 extruded from the die 12, and further near the roll 14. A press roll 16 and an embossing roll 17 are disposed facing each other to press the addition material 7 onto the film.

On the other hand, a roll 15 is provided near the second molding die 13 to adhere the extruded fastener 8 to the film and guide it to the next process. As shown in FIG. 4, this roll 15 has a function of guiding both sides of the fastener 8 to be fixed to the film 1.
11 indicates a cooling step.

In the present invention, the film 1 transferred through the roll 14 is extruded from the first molding die 12 and the appendages 7 such as the bead 2 and the strip 3 are formed on the roll 14.
4, and then moved between the press roller 16 and the embossing roll 17, where they are pressed and bonded.

Next, the film 1 to which the appendage 7 has been adhered is transferred onto the roll 15 on the second forming die 13 side, and a male claw is extruded from the second forming die 13 onto the film 1 moving on this roll 15. 4,
The fasteners 8 of the female claws 5 are welded together.

According to the present invention, the first forming die for forming the adduct and the second forming die for forming the fastener are separated and placed separately, and are mutually welded to the transfer film, so that the adduct can be extruded. Since the optimum temperature for forming the fastener and adhering it to the film can be divided into the optimum temperature for extrusion forming the fastener and adhering it to the film, the following effects can be obtained.

That is, since the fastener and the adduct have die temperatures suitable for their respective formation as described above, the adhesive heat retained after extrusion and the shape can be made as desired and adhered to the film. Further, since the pressure applied by the roll of the additional material to be adhered to the film is performed in a step before adhering the fastener, the adhesive roll 15 is not damaged.

Therefore, there is an effect that smooth adhesion can be performed without deforming or tilting the fastener on the roll 15. Furthermore, as described above, since the additive is first adhered to the film surface, the film surface around the adhesion point is heated. Therefore, when adhering a fastener in parallel to an adduct, the molding heat of the fastener itself is low because of the heat retention around the adduct. Fasteners and films can be glued to.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a plastic film to which a fastener and a plastic adduct have been adhered, Fig. 2 is an explanatory diagram of a conventional method of adhering a fastener and an adduct to the plastic film shown in Fig. 1, and Fig. 3 is a method of the present invention. FIG. 4 is a view taken in the direction of the arrow in FIG. 3. 1...Plastic film, 2...Belt, 3
... Strip piece, 4 ... Male claw, 5 ... Female claw, 7 ... Addendum, 8 ... Fastener, 12 ... First forming die, 13 ... Second forming die, 14 ... Joining roll, 15... Adhesive guide roll, 16... Press roll, 17... Embossing roll, 18... Extruder.

Claims (1)

[Claims] 1 a first molding die for extruding the additive;
In an apparatus in which a second molding die for extruding male and female claw plastic fasteners and a second molding die are individually installed in parallel in one extruder, the additional molding die is extruded from the first molding die having a higher molding temperature than the second molding die. After the material is loosened from the winding frame and bonded to the film surface moving on the bonding roll 14 provided near the first forming die, the film with the appended material is sent onto the embossing roll 17 and at the same time pressurized. The process of press-bonding the additive onto the film surface using the roll 16, and the process of completing the pressure bonding and sending the film provided with the additive onto the adhesion guide roll 15 provided near the second forming die; The method comprises the step of adhering a plastic fastener extruded from a second molding die having a lower molding temperature than the molding die to the film surface in parallel with the appendage of the film with the appendix by the heat retained in the molding of the fastener. A method of molding and adhering characteristic fasteners and additives to a film.