JPH0620907B2 - Sealed packaging bag - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hermetically sealed packaging bag in which an opening is heat-sealed.

[Conventional technology and its problems]

The packaging bag whose opening is heat-sealed is usually very strongly heat-sealed so that there is no defect such that the heat-sealing portion comes off during handling such as hot water treatment or transportation. For example, according to Japanese Agricultural Standards (JAS), when labeling retort foods, when the sample of the sealed part is cut out with a width of 15 mm in a pouch and the peel strength is measured, it must be 2.3 kg or more. Has been done.

However, when taking out the contents, it is necessary to open it, and the one that has been strongly heat-sealed as described above cannot be easily peeled off by hand, and is cut with scissors or a blade. However, if you do not have these tools at hand, opening them will be very time-consuming.

Therefore, a method has been adopted in which a tear (notch) is provided in the opening in advance, and the tear is used as a starting point, but the tear line is not linear, and there is a drawback that the opening is messy. In the distribution process, there is a drawback that the impact causes breakage from the cut end, impairs the hermeticity, and adversely affects the contents.

Therefore, an object of the present invention is to provide a packaging bag in which the opening can be easily peeled off by hand, and at the same time, the contents can be sufficiently protected in the processing process and the distribution process.

[Means for achieving the purpose]

To achieve the above object, according to the present invention, the heat-sealing portion provided in the vicinity of the opening of the packaging bag is provided with a recessed line extending over the fusion-bonded part and the adhered part, and the cross-sectional shape of the recessed line is formed. The depth is gradually increased from the outer edge toward the inner edge, and the outer edge is made into a zigzag bending line so that the inner edge is substantially linear. Furthermore, the edge of the opening is closed or shielded.

[Action]

When a deep groove extending over the fused portion and the adhered portion as described above is formed by pressurizing and heating, the peel strength from the inner edge to the outer edge of the groove becomes greater than the peel strength from the outer edge to the inner edge, Furthermore, since the outer edge is bent continuously and the adhesive line of the outer edge is zigzag with respect to the peeling direction, it can be easily opened from the outside of the opening, while it is easy from the inside of the packaging bag. A heat-sealed part that does not peel off is obtained.

In addition, the peel strength is a graph showing a change in load when the heat-sealed portion is cut out to a constant width (for example, a width of 15 mm) and the fused portion and the adhered portion are peeled (this is a heat-sealing curve). Say), the average value.

〔Example〕

First, a heat sealer hot plate for sealing the packaging bag will be described.

As shown in FIGS. 1 to 4, the printing surface 11 of the upper die 10
The ridge 12 is provided on the bottom surface of the lower die 20, and the printing surface 21 of the lower die 20 is flat. In the figure, H is a heater.

The ridge as a whole has a gentle mountain shape protruding in the direction of the outer edge 13. There may be more than one Yamagata.

The cross-sectional shape of the ridge 12 is such that the height gradually increases in the direction from the outer edge 13 to the inner edge 14.
As shown in FIG. 4 (a), the height gradually increases from the outer edge 13, but the cross-sectional shape may be such that it becomes flat midway and extends to the inner edge 14 as it is. As shown in the figure (b), the shape may be such that once the vertex 16 is reached, the height gradually decreases toward the inner edge 14. In this case, from the apex 16 to the inner edge 14
It is preferred that the slope towards the slope is steeper than the slope towards the outer edge 13.

Next, as shown in FIGS. 2 and 3, the inner edge 14 has a linear shape (although there may be some bending), and the outer edge 1
3 forms a zigzag bending line, the length of which is 30% or more longer than that of the inner edge 14.

The bending line of the outer edge 13 is not limited to the mountain shape, and is not limited to FIG.
As shown in (a), (b), (c), and (d), various shapes can be adopted, and a combination thereof may be used. Also, Fig. 5 (e)
As shown in, a part of the outer edge 13 (between the peaks) may coincide with the inner edge 14.

Furthermore, the outer edge 13 does not necessarily have to be bent in a zigzag manner over the entire length, and may be partially linear.

The above-mentioned convex strip 12 may be provided on the lower mold 20. Further, an elastic body 22 such as silicone rubber may be provided on the mating mold so as to correspond to the ridges of the upper mold or the lower mold.

FIGS. 6 to 9 show a method of sealing the packaging bag using the hot plate as described above.

As shown in FIGS. 6 and 7, first, notches 31 and 31 are provided on both sides of one end of a rectangular sheet 30, and when two folds are made along a fold line 32 closer to the one end than the center,
The extra portion becomes the flap 33. In addition, this sheet 3
In No. 0, the inner surface is a heat sealant layer.

Both side edge portions 3 of the sheet 30 thus double-folded
Heat-sealing 4, 34 creates a bag having an opening 35 at the end with the flap 33. At this time, cutout 3
At portions 1 and 31, the heat-sealing agent layer of the opposed side sheets that are overlapped is exposed. The bottom 32 'of the bag corresponding to the fold 32 may be heat-sealed together with the side edge 34.

Next, as shown in FIG.
8 along the outer surface of the bag so as to cover the notch 31 by bending along the line, and using the above-mentioned heat sealer hot plate as shown in FIG. As shown in FIG. 4, a chevron-shaped recess 36 is formed as a whole.

The recess 36 does not always have the same shape even with the same hot plate depending on the restoring property of the packaging bag material, shape retention, heat sealing conditions, etc. However, immediately after heat sealing, the depth of the recess is reduced. Over the fused portion and the adhered portion, and the cross-sectional shape of the concave line gradually becomes deeper in the direction from the outer edge 37 to the inner edge 38, and the contour of the outer edge 37 is longer than the inner edge 38 by 30% or more. Drawing a zigzag bending line. The inner edge 38 has a substantially straight shape with little bending.

In addition, unless the outer edge 37 is longer than the length of the inner edge 38 by 30% or more, peeling from the outer side, that is, easiness of opening is not good. This is because the bending ratio of the outer edge 37 is small.

When the heat sealing is performed as described above, the flap 33 is
Only the portion corresponding to the notches 31 and 31, that is, the small portion where the heat sealing agent layer is exposed as described above, is heat-bonded to the outer surface of the bag (see FIG. 8). Therefore, the flap 33 is fixed only on both sides of its end, and the other part is separated from the bag. When the separated portion is held by hand and pulled, the small adhesive portion in the notches 31 and 31 is easily removed, and the flap 33 can be returned to the free state as shown in FIG. 7.

As shown in FIG. 10, the flaps 33 may be omitted and the openings 35 may be heat-bonded in a dot shape to close the openings. In the figure,
Reference numeral 39 is a dot-shaped adhesive portion. In short, it is not limited to the dot shape, and the adhesive portion may be intermittently provided so that it can be easily peeled by hand.

As the material of the packaging bag, various materials can be selected as long as they can be heat-sealed and have some flexibility. It may be a single substance or a composite material. For example, a base material such as an aluminum foil provided with a heat seal layer is used.

The sealed packaging bag is not limited to the so-called flat bag as described above, and the bag may have any form such as a self-standing bag.

〔effect〕

According to the present invention, as described above, the heat-sealing portion of the hermetically sealed packaging bag is formed with a recessed line extending from the outer edge to the inner edge by applying heat and pressure, and the cross-sectional shape is changed from the outer edge to the inner edge. Since the inner edge is made to be gradually deeper and the inner edge is made substantially straight and the outer edge is made into a zigzag bending line, the peeling strength from the outside of the package is weakened and the package can be easily opened, while it can be easily opened. The peeling strength is increased, the contents can be sufficiently protected, and excellent sealing property and easy opening property, which have never been seen in the past, can be obtained.

Further, since the opening of the bag is closed or shielded, it is possible to prevent dust from entering the opening, and at the same time, to protect the heat-sealing portion, which brings about many effects.

[Brief description of drawings]

FIG. 1 is a cross-sectional diagram of the heat sealer hot plate, FIG. 2 is a plan diagram of the upper mold, and FIG. 3 is a partially enlarged perspective view of the upper mold.
The figure is an enlarged cross-sectional view taken along line 4-4 of the above, FIG. 5 is a plan view showing the contours of the ridges provided on the upper mold, and FIG. 6 is a developed perspective view of a sheet forming a bag, FIG. FIG. 8 is a perspective view showing a bag forming process, FIG. 8 is a front view of a completed bag, FIG. 9 is an enlarged sectional view showing a sealed state of the bag, and FIG. 10 is a front view showing another embodiment of the bag. Is. 10 ... upper mold, 11 ... impression surface, 12 ... convex stripe, 13 ... convex stripe outer edge, 14 ... convex stripe inner edge, 20 ... lower mold, 21 ... impression surface, 22 ... ... Elastic body, 30 ... Sheet, 31 ... Notch, 32 ... Crease, 33 ... Flap, 36 ... Recess, 37 ... Outer edge of recess, 38 ... Inner edge of recess.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Shown 57-123754 (JP, U) Shown 54-142222 (JP, U) JP 57-7975 (JP, B2)

Claims (1)

[Claims] 1. A heat-sealing portion provided near an opening of a packaging bag,
A groove is formed extending over the fused portion and the adhered portion, and the cross-sectional shape of the groove is gradually deepened in the direction from the outer edge to the inner edge, and the outer edge is formed into a zigzag bending line to substantially define the inner edge. A hermetically sealed packaging bag which is linear and has the opening edge closed or shielded.