JPH0661846B2 - Manufacturing method of fusing seal bag - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a fusible seal bag.

[Prior Art] Conventionally, when a bag is manufactured from a plastic film, a method has been used in which the plastic film is cut into a predetermined size and the periphery of the cut surface is sealed with a seal bar or a seal roll. In such a method, in order to prevent the plastic film from adhering to the seal bar or the seal roll, a heat-sealable resin is used for the innermost layer, and the innermost layer resin that does not adhere to the seal bar or the seal roll is used as the outermost layer. A plastic film having a multilayer structure using a resin having higher heat resistance has been required.
On the other hand, a fusing seal bag formed by using a long plastic film that is folded back from approximately the center in the width direction and cut at a predetermined distance in the longitudinal direction with a heating blade and simultaneously melt-sealed is a single resin layer. It has a merit that it can be manufactured from a film made of, and can be manufactured at low cost.

[Problems to be Solved by the Invention] In the fusing seal bag made as described above,
At the time of cutting, since only the cut surfaces of the plastic film that are in contact with both sides of the heating blade are heat-sealed, the left and right ends of the bag have the advantage that a seal portion having substantially no adhesive width is formed. The formed bag had the drawback that due to the elasticity of the plastic film itself during cooling, it was easily peeled off at the fusing seal portion near the folding line and a hole was easily opened.

The present invention has been made in view of the above drawbacks, and an object thereof is to provide a fusing seal bag in which peeling or perforation of a fusing seal portion near a folding line does not occur even when the fusing seal is performed, and It is to provide a method for manufacturing a fusion-cut seal bag.

[Means for Solving the Problems] The above object of the present invention is to fold a long stretched plastic film from approximately the center in the width direction, cut it with a heating blade at predetermined intervals in the longitudinal direction, and weld the cut surface at the same time. The method for producing a fusing-sealing bag is characterized in that the stretched plastic film is coated with a heat-sealing agent along the periphery of the folding line above the production method of the fusing-sealing bag.

[Operation] The method for producing a fusion-sealed bag according to the present invention has the above-described structure, and in particular, by using a stretched plastic film coated with a heat-sealing agent along the periphery of the folding line, the folded plastic film is folded back as compared with the case of using a stretched plastic film alone. The fusing seal portion near the line can be firmly adhered at a low temperature, and as a result, a fusing seal bag without peeling of the seal portion and perforation can be manufactured.

[Example] An example showing a preferred embodiment of the present invention will be described below with reference to the drawings.

According to FIG. 1, the fusing seal bag of the present invention uses, for example, a long stretched plastic film 1 of uniaxially stretched polypropylene or biaxially stretched polyethylene terephthalate,
Along the lengthwise direction, the heat-sealant 2 is pre-applied to the approximately central portion in the width direction, and the folding line 3 is formed by folding back from the approximately central portion. It is formed by intermittently cutting the moving film 1 with a heating blade 6. At this time, since the heating blade 6 is heated to a temperature equal to or higher than the softening point of the film 1,
At the same time as the cutting, the film 1 is welded on both sides to form a fusing seal portion 4. Further, since the heat seal agent 2 is applied to the vicinity 5 of the fold line of the fusing seal portion 4, the fusing line is further firmly welded by cutting the heating blade 6, and a fusing seal bag having no peeling or perforation is formed.

In the present invention, a well-known heat seal agent can be used as the heat seal agent, for example, an ionomer resin (ionic copolymer of ethylene / acrylic acid copolymer), ethylene- (meth) -acrylic acid. Esters and the like are preferably used. All of these heat sealing agents adhere firmly at a lower temperature than the stretched plastic film. Therefore, a sufficient adhesive force can be obtained without further pressing the vicinity of the folding line with a roller or the like.

Further, by using a long stretched plastic film, the above-mentioned fusing and sealing bag having high strength can be continuously manufactured.

FIG. 2 shows a plan view of the fusing seal bag manufactured by the method of the present invention, and FIG. 3 shows a sectional view taken along the line AA of the fusing seal bag shown in FIG. As is clear from FIG. 2 and FIG. 3, the stretched plastic film 1 in which the heat sealant has been applied to the inside of the periphery of the folding line in advance is folded back from approximately the center in the width direction to form the folding line 3, and The left and right ends of the stretched plastic film 1 are melt-sealed by heating blades to form a fusion-cut seal portion 4 having substantially no width. Since the heat seal agent is applied in the vicinity of the bottom of the fusing seal portion 4 in advance, the heat sealing agent adhering portion 5 is formed by being particularly strongly adhered during the fusing seal.

Although a preferred embodiment of the present invention has been described in the above embodiment, the present invention is not limited to the above embodiment within the scope of the present invention. For example, the heat sealing agent may have a predetermined width along the folding line 3. It is not always necessary to apply all. Other improvements or changes can be made without departing from the scope of the present invention.

[Effects of the Invention] As described above, according to the method for manufacturing the fusible seal bag of the present invention, since the heat seal agent is applied in advance to the periphery of the folding line, the fusible cut occurs when the plastic film is blown by the heating blade. The vicinity of the folded line of the seal portion is firmly adhered, so that a strong fusing seal bag without peeling of the seal or perforation of this portion is formed. Further, according to the method of manufacturing the fusion-sealing bag of the present invention, since the fusion-sealing is performed, it is possible to manufacture even a heat-sealable resin single layer film,
Moreover, there is an excellent advantage that a seal portion having substantially no width can be formed on both sides.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a manufacturing process of a first embodiment of a method for manufacturing a fusing seal bag of the present invention, and FIG. 2 is a plan view of an example of a fusing seal bag formed by the present invention, FIG. Shows a cross-sectional view taken along the line AA in FIG. 1 ... Plastic film 2 ... Heat sealant 3 ... Folding line 4 ... Fusing seal part 5 ... Heat sealant adhesive part 6 ... Heating blade

Claims (1)

[Claims] 1. A method for producing a fusible seal bag, which comprises folding a long stretched plastic film from approximately the center in the width direction, cutting it with a heating blade at a predetermined distance in the longitudinal direction, and welding the cut surface at the same time. A method for producing a fusion-sealed bag, wherein the stretched plastic film is coated with a heat-sealing agent along the periphery of the folding line.