JPH068949A - Sealed bag - Google Patents

Abstract

PURPOSE:To provide a sealed bag which can be easily cut by the force of fingers from an optional area on the end edge of an overlapped type heat-sealed part of the sealed bag while the strength of the film is not spoiled, and to which foreign matter is not mixed in at the time of processing. CONSTITUTION:The title sealed bag is made by heat-sealing a film 8 at least at a non-end edge part, and for the heat-sealing method, both ends of the film 8 are overlapped while being crossed, and heat-sealed parts 5, 6 are made not to protrude. As the feature of such a sealed bag, at an end edge 2 of the heat- sealed part or the end edge 2 of the outer edge of the heat-sealed part, a large number of scars 1 are provided for the title sealed bag.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processed and easily opened plastic sealed bag which can be opened by the force of fingers without impairing the practical strength of the bag.

[0002]

2. Description of the Related Art Recently, a plastic film and a laminated film of a plastic and a metal such as aluminum foil and other materials such as paper are lightweight and have excellent airtightness, high strength, convenient handling, and sealing. In particular, no adhesive is required, and it suffices to simply heat-seal it.
It is used as a sealed bag for various types and shapes of products such as small items such as liquids, powders, pastes and solids.

[0003] In these sealed bags, the advantage of the material is that, when the bag is opened, resistance to tearing is conversely exhibited, and it is difficult to tear. The film for the sealed bag is tough, but once a scratch occurs, the scratch tends to propagate, so one scratch is made on the edge of the bag in advance. You can just open it.

For this reason, a method is used in which a cut (I notch) having a length of 2 mm or more in the transverse direction is provided in advance on the edge of the film at the fused portion. In this case, the edge of the bag is torn. There is a drawback that it is difficult to find out if the mouth is provided. In addition, a V-shaped scratch (V notch) is also provided on the edge portion, and although this method makes it easier to find the break, a V-shaped scratch is required when a large amount of bags are made and filled. Cut pieces tended to scatter and adhere to packaged products, or worsen the work environment.

In any case, since the breakage points of these methods are limited to one place, that part is not always the desired part, and the breakage propagates in an undesired direction,
There were inconveniences such as the contents scattered around. In addition, since it is a large notch (minimum length 2 mm), if it is processed into a film before bag making, it is easily broken and bag making is impossible.

Further, the knotted bag is a so-called pillow type having a bag seal provided in the central portion in the vertical direction as shown in FIGS. 4 and 5, and the fusing method is to overlap both ends. In the case of the so-called overlap method in which the fusion-bonded portion does not project, even if the notch is opened, breakage tends to stop at the fusion-bonded portion, and only half of the bag tends to open. In this case, it is inconvenient to take out the contents through the narrow opening.

[0007]

As a method of cutting from an arbitrary portion of the edge line of a hermetically sealed bag, a method of forming perforations at regular intervals with a sharp blade lacks a part of the film and scatters or cuts the blade. It causes clogging and has a small effect of starting cutting. Although the method of making holes with a needle does not cause a drop, the effect of initiating cutting of the film is small, and the portion where the crack occurs is not constant, so that the tear tends to run in an undesired direction.

Further, the processing into a film for easy opening has an influence on the practical strength of the film, and the film is damaged during the processing step of the film, the bag-making step, the transportation, or the storage, Alternatively, the sealed bag filled with the contents may be damaged. This is a particular problem when a thin film or a film made of a material having a relatively low strength is used.

Therefore, no omission occurs, no foreign matter enters,
There has been a demand for a sealed bag having an ideal scar that does not lower the practical strength of the film and that can be opened from an arbitrary site with the force of a finger, and a film for producing the same.

According to the present invention, the non-edge portion of the hermetically sealed bag is provided at the end portion by utilizing the scars provided at the end portion of the overlap type fusion-bonded portion or the edge portion of the outer edge of the fusion-bonded portion. With I-notch or V-notch, it can be easily cut by hand force
(See also), and yet to provide a sealed bag that does not impair the strength of the film and does not contain foreign matter during processing.

[0011]

According to the present invention, there is no possibility that foreign matter such as film fragments is mixed in the processing step.
It is intended to provide a certain cutting start effect in spite of minute scratches by arranging specific scratches on a portion of the film which will be a fusion-bonded portion after bag making or an edge portion.

The scar of the present invention has an elongated shape in which the length is longer than the width, and the length thereof is 0.5 mm or less, preferably 0.
It is 3 mm or less and 0.1 mm or more. As shown in FIG. 1, the scratches 1 are arranged transversely to the edge line 2 of the edge portion. The tips 3 and 4 of the scar 1 have an acute angle, and a crack is generated at this portion. There are few cracks in other parts of the scar. If such a group of scars exists on the edge line,
It begins to tear from the inner tip 4 of the scar 1. Edge line 2
2 is present inside of the scratches, when stress as shown by the arrow in FIG. 2 is applied, the scratches start to break from the tip 3 on the edge line side toward the edge line 2 as shown by the broken line arrow in FIG. After the part is torn, as shown in FIG. 3, it begins to tear in the transverse direction from the tip 4 of the other scar.

Therefore, the elongated scratches arranged in the transverse direction on the edge line 2 of the scratch 1 is ideally 9 with respect to the edge line.
0 °, but 90 ° ± 20 °, preferably 90 ° ± 1
At 5 °, the object of the present invention is achieved.

A flawless defect is a localized damage to the film caused by being spread or partially cut, and in producing these scratches, no fragments are separated from the film. Say. The scars used in the present invention are such a large number of scars, and the shape of the scars is not particularly limited, and may be other linear scars having the shape shown in FIG. These scratches often penetrate the base film, but they may be penetrated or non-penetrated as long as a cutting start effect can be expected.

The site where the scars are provided is the edge of the fusion portion of the overlap type bag or the edge of the outer edge of the fusion portion. If the film is thick and tough, it must be provided on the edge line. However, if the film is thin, it is desirable that the area 0.5 to 3 mm inside the edge line. In the present invention, the overlap-type fusion-bonded portion of the bag may be on the edge line of the cross-overlapped portion at both ends of the film, or may be inside the non-fusion-bonded portion.

As a form of the bag, there is a three-way seal type bag as shown in FIG. Reference numeral 5 is a vertical fusion portion, 6 is a horizontal fusion portion, and A is a scar group. FIG. 5 is an enlarged cross-sectional perspective view of FIG. In this case, this is a so-called overlap-type fusing method in which the films 8 to be fused are brought close to each other in the opposite direction and overlapped, and the fusing part does not project from the bag surface. Conventionally, such a bag was provided with an I notch or a V notch in the lateral fusion portion, but when attempting to break across a slender bag, the break stops at the longitudinal fusion portion and only half It does not open, but it is forced out through a narrow opening. However, if the scars according to the present invention are provided at the end edge portion of the vertical fusion-bonded portion 5, the tear can be crossed without stopping at the fusion-bonded portion. 20 is an I notch. As described above, in the present invention, it is possible to use the conventionally known scratches such as the I notch and the V notch.

The scars according to the present invention may be provided over the entire length of the edge portion, but may be provided intermittently or locally as shown in FIG. 4, for example.

The film for producing the hermetically sealed bag of the present invention may be one which can be heat-sealed and has a strength capable of withstanding distribution and storage, but nylon, polyester, oriented polypropylene and the like are preferably used. . Since these films are tough, they cannot naturally start to break with the force of the fingers. For bag making, generally, a material obtained by laminating another plastic film capable of being heat-sealed on these base material films is used. As the other heat-sealable plastic film, an olefin resin such as low density polyethylene, a polyethylene-vinyl acetate copolymer, or the like is used. The heat fusion temperature varies depending on pressing pressure, pressing time, film thickness, type, etc., but is performed at 80 to 180 ° C., usually 120 to 150 ° C., and at such a temperature, a molten state, at least a semi-molten state is obtained. Is preferred.

The film used for producing the hermetically sealed bag of the present invention includes a plastic film laminated in this manner and processed with the above-mentioned scars, but the toughness before laminating the heat-fusible film is laminated. It also includes those obtained by subjecting the film base material to scratch processing. That is, when a base film having a large number of scratches is laminated with a heat-sealable film or other film, the scratches are covered by these laminated films, but a tough film that actually tears is a base film. Therefore, even if the scratch is covered with another film, the object of the present invention can be sufficiently achieved if the scratch of the present invention is provided on the base film.

As a tool for providing such a scar group,
Although not particularly limited, a large number of elongated cutting edges may be provided on the circumferential surface of the metal roll or the flat surface of the metal plate. For example, as shown in FIG. 7, when the metal surface 9 is cut into a pseudo-triangular shape and the base of the pseudo-triangular shape is used as a central axis, a metal part that is cut and separated from the metal surface is erected. Protrude, and the cut portion remains as a recess 11. It is preferable that the surface of the protrusion 10 on the recessed side, that is, the angle of the cut surface 12 with respect to the metal surface is 60 ° or more and 90 °. One or more rows of such protrusions are linearly arranged, and the metal is quenched and used. FIG. 7 is a perspective view of the processing roll 13 provided with such a protrusion on its circumferential surface, and FIG. 8 is an enlarged plan view of a portion indicated by a chain double-dashed line in FIG.

When the film is pressed by the projections 10 as shown in FIG. 6, the peripheral edge of the cut surface 12 acts as a cutting edge to form an elongated scratch 1 on the film 8 and both scratches 1 are formed. The tip is sharp and there are cracks. In the case of a circular cutting edge, the shape of the scar is random and may be a semicircular shape, a triangular shape, a branched shape, or the like. In this way, since the portion where the acute angle of the scratch is generated is not constant, the scratch obtained by the circular blade edge has a small cutting start effect.

FIG. 9 is an explanatory view showing an example of processing a film using the processing roll 13 shown in FIG. The processing roll 13 and the pressing roll 14 are rotating in the opposite directions at the same peripheral speed while contacting at one place. The film 8 passes through the contact portion of both rolls. At this time, the film 8 is pressed by the projections 10 of the processing roll 13 and scratches 1 as shown in FIG.
Arranged. Reference numeral 15 is a raw material for unwinding the film.

[0023]

【Example】

Example 1 A composite film (total thickness 70μ) having a width of 620 mm and a stretched polypropylene film (thickness 30μ) used as a base material layer and polyethylene films (20 μm in thickness each) as heat-sealing layers on both sides thereof, As the processing roll 13, the protrusions shown in FIG. 7 having a maximum width of 0.5 mm, which are arranged in a zigzag pattern in seven rows with a center-to-center distance of 0.7 mm, are used.
A total of 11 rows of scratches were formed linearly in the lengthwise direction of the film at a location 10 mm from both edges in the width direction of the film and at an equal interval of 60 mm inward from the edges. After cutting the central part of the group and removing the ears, it is wound into a roll shape, width 600 mm, length 100
A 0 m roll-shaped film was obtained. At the time of winding, the wounded portion was slightly bulky, but it could be wound without any trouble.

The film thus obtained is one in which scratches are arranged at equal intervals of 60 mm on both edges and inside thereof. After cutting the center of each scar group with a 10-series automatic bag-filling machine using this, instant coffee 2
An envelope stick type stick packaging bag was filled while filling each g.

In the obtained bag, scratches are provided on both ends of a film which is formed by overlapping and overlapping the envelope sticking type seal portions.

There were no troubles in which the film was broken from scratches during the bag making process, transportation and storage. At the time of use, the bag will be opened from the notch provided in the top seal (L-shaped seal) of the bag, but since the film edge edge facing the tear direction of the envelope sticking seal part has scratches, the progress of tearing will progress. I was able to tear it to the end smoothly without interruption.

Further, even after the filling, there was no accidental tear from the envelope sticking seal portion during transportation or handling.

[0028]

EFFECTS OF THE INVENTION According to the present invention, the force of a finger is applied by the I notch or V notch provided at the end by utilizing the scars of the fused portion at the non-edge portion without impairing the practical strength of the film. It is possible to provide a sealed bag that can be opened.

[Brief description of drawings]

FIG. 1 is a plan view of a film end portion.

FIG. 2 is an explanatory diagram of a breaking mechanism.

FIG. 3 is an explanatory diagram of the same.

FIG. 4 is a perspective view of a sealed bag.

5 is an enlarged transverse perspective view of FIG.

FIG. 6 is an enlarged view of a protrusion of a scarring fixture.

FIG. 7 is a perspective view of a processing roll-shaped scarring attachment.

8 is an enlarged plan view of the circumferential surface of FIG. 7.

FIG. 9 is an explanatory view showing an example of film processing.

[Explanation of symbols]

 1 Scratch 2 Edge line 3,4 Tip 5 Longitudinal fusion part 8 Film 10 Protrusion 11 Dimple 12 Cut surface 13 Processing roll A Scratch group

Claims (1)

[Claims] 1. A sealed bag formed by fusing a film at least at a non-edge portion, wherein the fusing method is such that both ends of the film are crossed and overlapped so that the fusing part does not protrude. A hermetically sealed bag, characterized in that a large number of scratches are provided on an edge portion of the fused portion or an edge portion of an outer edge of the fused portion.