JPH11321887A - Unsealing mechanism for heavy duty synthetic resin bag and bag using the mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form, near a seal line, rupture lines in a specific shape having a part of the seal line as its one side, which zones a specific area, therefore, unseal without a tool such as a cutter and facilitate an unsealing job, and to eliminate the use of other unsealing material and, therefore, facilitate recycling. SOLUTION: An unsealing mechanism A comprises a seal line 2 for it, two straight perforation lines 3 and 4 provided in the shape of a triangle having a part of the seal line 2 as its bottom, and a perforation line 5 in the shape of a circular arc provided in the apex part of the perforation lines 3 and 4. It is preferable that the angle between the two straight perforation line 3 and 4 (apex angle) θ be 50-70 deg. and the radius R of the circular-arc perforation line 5 in the apex part be about 10-15 mm. In order to unseal the package body, a part inside the apex part of the triangle 7 is pushed with a thumb to rupture the circular-arc perforation line 5 and, further, the straight perforation lines 3 and 4 on both the sides as well. By this constitution the need for a cutter is eliminated the unsealing is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opening mechanism for a synthetic resin heavy bag and a heavy bag using the same. The heavy bag referred to herein is a bag having relatively high strength used for packing powder or granules of cereals, fertilizer, culture soil, synthetic resin, industrial chemicals, and the like.

[0002]

2. Description of the Related Art Such a synthetic resin heavy bag is formed by closing one end of a tubular synthetic resin sheet by heat sealing to form a bottom. The opening at the other end is filled with the contents and then closed by heat sealing to form a package. In general, the filling amount per bag is relatively heavy, ranging from several kilograms to about 15 to 30 kg. Therefore, the thickness of the heavy bag is 100 to 200 μm, which is considerably thicker than a normal garbage bag or the like. Therefore, it cannot be torn off by hand, and the seal is opened by cutting using a knife, scissors, sickle or other blade.

[0003]

In the work of handling heavy bags, they are stacked and unloaded with both hands. Therefore, the handling operation is complicated, such as picking up the blade every time opening, opening the blade, and then storing the blade in order to discharge the contents from the heavy bag. In addition, we take great care in handling blades. Note that it is conceivable to configure the opening mechanism using other opening materials such as paper, but in that case, the materials are different, so that it is difficult to recycle. An object of the present invention is to make it possible to easily open a heavy bag without using a tool such as a knife. A further object of the present invention is to provide a heavy bag that can be recycled in the same manner as before without adding another opening material.

[0004]

According to a first aspect of the present invention, there is provided a plastic bag opening mechanism for a synthetic resin double bag, comprising: a seal line for the synthetic resin double bag; And a break line formed so as to divide a predetermined region with the portion as one side. In such an opening mechanism, it is preferable that the break line is formed to have a substantially triangular shape with one side of the seal line as one side (Claim 2). (Claim 3). The apex angle of the triangle is 50 to 70.
(Degree). Further, it is preferable that the break line has air permeability, for example, a perforation (claims 5 and 6). It is preferable that the perforated hole is a long cut in the cutting direction (claim 7). If air permeability is not required, the perforations may be covered with a water-resistant and easily rupturable coating film.

The heavy bag made of the synthetic resin of the present invention (claim 9)
Is characterized by having any one of the opening mechanisms described above.

[0006]

The opening mechanism according to the present invention is characterized in that the inside of a heavy bag is filled with a powder or a granular material, and a finger or the like is positioned inside a breaking line for dividing a predetermined area. , The breaking line can be broken.
Then, by further breaking along the break line to break until it hits the seal line, the predetermined area is opened. Then put your finger through the opened opening, pick the sheet around the heavy bag with both hands, pull it back and forth, and from the intersection of the break line and the seal line, the seal line You can break along. Therefore, it can be easily opened without using a tool such as a knife. When the region is located at the center, the region generally opens right and left from the center, so that the region is fully opened. However, it is also possible to open only one side from the center.

In the case where the region has a substantially triangular shape with a part of the seal line as a base (claim 2), a force can be applied intensively by pressing a vertex with a finger. Therefore, the first fracture is easy. Also, since the line of intersection between the break line and the seal line has an acute angle, when the seal line starts to be broken, it is easily broken. In the opening mechanism in which the triangular apex is formed in an arc shape (claim 3), when the thumb or the like is pressed against the apex, the portion can be more easily broken. Further, in the opening mechanism having a triangular apex angle of 50 to 70 degrees (claim 4), the force is easily concentrated on the vertex. Moreover, after opening in a triangular shape, the edge of the opening and the sealing line are 55
Since it is about 65 degrees, it can be more easily opened on both sides along the seal line. In the case where the breaking line has air permeability (claim 5), the air in the bag is degassed after filling without separately forming ventilation holes, so that the stacking stability is increased. Further, it is possible to avoid the expansion of the residual air generated at high altitudes. When a perforation is used as the break line (claim 6), the break line can be easily formed. In the case where the perforation hole is formed as a long cut in the cutting direction (claim 7), since the cutting direction is directional, the break is hard to be separated from the perforation line and is easily broken along the perforation. When the perforation is covered with a water-resistant and easily ruptured coating film (claim 8), the air permeability is lost, but water and moisture hardly penetrate through the perforation, and the filler can be protected from moisture. .

The heavy bag made of the synthetic resin of the present invention (claim 9)
Is provided with any of the above-described opening mechanisms, so that the opening can be performed without using a tool such as a blade, and the opening operation is easy. Also, since no other opening material such as paper is used, recycling is easy as before.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an opening mechanism and a double bag according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an embodiment of the opening mechanism of the present invention, FIG. 2 is a plan view of a heavy bag provided with the opening mechanism, FIG. 3 is a process diagram showing a filling operation into the heavy bag, and FIG. FIG. 5 is a process diagram showing an opening procedure of the opening mechanism of FIG. 1, FIG. 5 is a perspective view showing another opened state of the heavy bag, and FIGS. 6 and 7 show still another embodiment of the heavy bag and the opening mechanism of the present invention. It is a top view.

The opening mechanism A shown in FIG. 1 can be provided at the center of the sealing line 2 of the heavy bag 1 as shown in FIG.
The heavy bag 1 was closed and formed into a bag shape by flatly folding a seamless synthetic resin tubular sheet flat and heat-sealing the upper and lower two sheets 1a and 1b at the opening at one end. Things. The seal wire 2 is somewhat harder than the other parts. The opening mechanism A shown in FIG. 1 includes a seal line 2 and two straight perforated lines 3 and 4 provided to form a triangle having a part of the seal line 2 as a base.
And an arc-shaped perforation line 5 provided at the apexes of the perforation lines 3 and 4. The perforation lines 3, 4, 5 are formed on the respective sheets 1a, 1b. Note that a tubular sheet having a seam can also be used. When using a tubular sheet formed by biaxial stretch blow molding and having a directionality in tearability, a perforated line 3,
It is preferable to match the direction of tearing easily with the directions of 4 and 5.

The angle (vertical angle) θ between the two linear perforation lines 3 and 4 is preferably 50 to 70 degrees, particularly preferably about 60 to 62 degrees. If it is less than 50 degrees, the apex portion is not easily broken. Further, the triangle becomes vertically long and the angle between the break line and the seal line increases, so that the progress of the break from the break line to the seal line is not smooth. Conversely, if the apex angle exceeds 70 degrees,
When the vertex is pressed with a finger, the progress of the tear may deviate from the perforation lines 3 and 4 and break at an angle close to a right angle to the seal line 2. The radius R of the arc-shaped perforation line 5 at the apex portion is preferably about 10 to 15 mm, particularly 12.5 mm.
mm is preferable. If it is less than 10 mm, the radius is smaller than the radius of the thumb, so that it is difficult to apply a force to the tip when pressed with the thumb, and the initial opening is difficult. Conversely, when the radius R exceeds 15 mm, the stress concentration at the tip becomes weak,
In that case, it is difficult to break. The perforations may be provided with round holes at intervals, but it is preferable to give directionality as the shape of the cut extending in the cutting direction. In that case, the perforation length is preferably about 0.5 to 1.5 mm, more preferably about 1 mm. If it is less than 0.5 mm, it is difficult to work and it is hard to break. If it exceeds 1.5 mm, the granular content tends to spill, and the strength tends to be weak. The perforation interval is preferably about 3 to 5 mm, and most preferably about 4 mm. If it is less than 3 mm, the strength tends to be weak, and if it exceeds 5 mm, it is difficult to break.

The perforation lines 3, 4, and 5 can be provided at once by pressing with a mold from one surface side, for example, in the state of a tubular sheet folded flat. In that case, since the perforated line is formed on each of the sheets on both sides of the bag, the bag can be opened from either side.

The width of the seal line 2 may be the same as that of a conventional heavy bag, for example, about 5 to 8 mm. The synthetic resin sheet constituting the heavy bag 1 is preferably a polyolefin-based resin such as polyethylene, polypropylene, and ethylene copolymer, and particularly preferably polyethylene. The thickness of the sheet varies depending on the application and the filling amount, but in the case of a heavy bag with a filling amount of 25 kg made of polyethylene, the thickness is 120 to 18 mm.
It is about 0 μm. The length L of the bottom side of the triangle 7 of the opening mechanism A is a portion that triggers the so-called boundary cut at the seal line 2, so that regardless of the size of the heavy bag,
For example, it is about 30 to 100 mm, preferably about 60 mm.

As shown in FIG. 3, the heavy bag 1 provided with the opening mechanism A constructed as described above is filled with the contents 9 from the upper opening 8 with the bottom having the sealing wire 2 facing downward. Then, the package is closed by sealing means such as heat sealing to form a package. When the contents are filled in this manner, the weight of the contents presses the sheet from the inside, but since the area of the triangle 7 is small, it is not broken without permission. Also,
In the case where the contents are filled and sealed, in a heavy bag (a so-called no-pin type) having no deaeration hole, air is sealed inside, so that the bag may become unstable when stacked. Further, when the heavy bag filled with the contents and sealed is transported to a highland where the air pressure is low or a region where the temperature is high, the residual air in the bag expands and the stacking becomes more unstable. For example, the general perception is that a 15% expansion is observed at a temperature difference of 20 degrees. In the case of a heavy bag in which the perforation lines 3, 4, and 5 are formed, the air in the bag is freely evacuated from the perforations, so that the above problem can be avoided.

In order to open the package 10, as shown in FIG. 4, the sealing line 2 is vertically set so that the sealing line 2 is on the upper side, or the sealing mechanism 2 is horizontally set so that the opening mechanism A is on the upper side. Press the inside of the vertex of triangle 7 with your thumb. Then, since the sheet is stretched depending on the contents, the arc-shaped perforation line 5 is broken, and the linear perforation lines 3 and 4 on both sides are further broken.

After the opening 11 having a triangular shape is formed, a finger or the like is put into the opening 11 so that the sheets 1a and
When the user picks 1b and pulls it forward and backward (in the directions of arrows P and P), it opens on both sides along the seal line 2. At this time, since the perforation lines 3 and 4 are inclined at an acute angle with respect to the seal line 2, the force concentrates on the apex portion, and the seal can be easily opened along the seal line 2. As shown in FIG. 5, only one side can be opened from the triangular opening 11. Seal wire 2
Is based on the difference between the hardness of the sealing wire 2 and the hardness of the adjacent portion, that is, the so-called “boundary break” principle. Therefore, it can be opened straight without bending. After opening, the contents are taken out by turning the heavy bag 1 obliquely or upside down.

The heavy bag 1 provided with the opening mechanism A as described above.
Does not require knives, scissors, sickles, or other knives when opened, and can be opened easily and with a straight line. Therefore, the opening operation can be performed efficiently.
Further, even when a heavy object is filled, the perforation line is not broken without permission.

If the sheet on one side of the bag is broken along the seal line, the heavy bag 1 can be opened. However, if the sheet on the opposite side also breaks along the seal line, the heavy bag 1 can be opened from the seal line. The outer part is separated as a relatively strong string. Therefore, when taking out only a part of the filling material and storing the rest in the heavy bag 1, the opening may be squeezed and tied with a string or the like. is there.

In the above-described embodiment, a perforation line is employed as a break line, but a break line may be formed by providing a linear groove or a ridge by heat or mechanical processing. However, perforations are most preferred because strength and tearability can be accurately adjusted. When a perforated line is used as the break line, there is an advantage that the air inside can be degassed from the perforated line, but water or moisture may enter the bag from the perforated line. for that reason,
In the case where the filler is a powder or a granular material which solidifies due to moisture, it is preferable to form a perforated line and then cover the perforated line with a water-resistant and easily breakable coating film. To form such a coating film, for example, a film-forming resin such as rubber or a polyolefin copolymer dissolved in a volatile solvent, or a varnish is sprayed,
It may be applied or printed and dried.

In the above-described embodiment, the two break lines are provided in a triangular shape, but may be formed in other shapes such as a trapezoidal shape or a square shape. However, even in that case, it is preferable to provide an arc-shaped breaking line that is slightly larger than the shape of the finger. Further, it is preferable that the portion connected to the seal wire is connected at an angle of about 55 to 65 degrees.

In the above-described embodiment, since the unsealing mechanism is provided on each of the sheets on both sides, there is an advantage that the unsealing can be performed from either side. However, it may be provided only on one sheet. The opening mechanism is preferably formed at the center of the seal line, so that the front and rear sheets can be sufficiently opened (see FIG. 4). However, the opening mechanism of the present invention is not limited to this, and may be shifted to one side. Also, it may be provided near one or both corners. Further, a break line may be provided at each of the upper and lower ends of the heavy bag 1 (see FIG. 6). In the case of providing at the upper end, an opening mechanism is constituted by a seal line and a break line formed after filling the contents. When it is provided at the upper and lower ends, it can be opened from both upper and lower sides.

In the opening mechanism B shown in FIG. 7, two straight perforated lines 3 and 4 forming a triangle having a part of the seal line 2 as a base, and an arc-shaped perforated line 5 provided at the apex thereof.
In addition, a perforated line 5a having a somewhat smaller radius and a third circular perforated line 5b having a smaller radius are formed at some intervals. Although there are individual differences in the shape and size of the finger, the opening mechanism B that is easy to open for any person by adding two or three arc-shaped perforated lines 5a and 5b having different radii as shown in FIG.
Can be provided.

[0023]

[Example] Made of polyethylene sheet having a thickness of 0.15 mm,
In the center of the sealing part of the heavy bag of 450mm in width and 650mm in height,
A device provided with an opening mechanism in an isosceles triangular shape (vertical angle 62 degrees) having a base length of 60 mm was prepared. The break line shall be a perforated line with a length of 1 mm and a gap of 4 mm.
The shape was a 2.5 mm arc. This heavy bag with opening mechanism
5 kg of advanced chemical fertilizer was filled, and the opening was heat-sealed with an impulse seal.

A so-called horizontal drop test was conducted in which the obtained package was dropped many times from a height of 1.5 m in a horizontal state using a testing machine. There was no problem and no tears occurred. Further, when a test of dropping in the side direction by hand drop was performed once, there was no problem at all. Further, vertical drop tests by hand dropping were performed once each with the opening mechanism part on the upper side and the lower side, and there was no problem at all.

After completion of the drop test, the first rupture could be easily made along the perforation by pressing the triangular vertex with the thumb. Further, by pushing along the perforation line with a finger, the seal portion could be easily broken along the perforation line. Furthermore, a finger was inserted into the obtained triangular opening and pulled back and forth, so that it could be easily opened along the seal portion. Although the triangular portion was left, the operation of taking out the contents from the heavy bag could be performed simply as in the conventional case.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of an opening mechanism of the present invention.

FIG. 2 is a plan view of a heavy bag provided with the opening mechanism of FIG.

FIG. 3 is a process chart showing an operation of filling the heavy bags of FIG. 2;

4 is a process chart showing an opening procedure of the opening mechanism of FIG. 1;

FIG. 5 is a perspective view showing another opened state of the heavy bag of FIG. 1;

FIG. 6 is a plan view showing another embodiment of the heavy bag provided with the opening mechanism of the present invention.

FIG. 7 is a plan view showing another embodiment of the opening mechanism of the present invention.

[Explanation of symbols]

 A Opening mechanism 1 Double bag 2 Seal line 3 Perforated line 4 Perforated line 5 Perforated line B Opening mechanism 5a Perforated line 5b Perforated line

Claims (9)

[Claims] 1. A synthetic resin comprising: a sealing line of a synthetic resin heavy bag; and a break line formed in the vicinity of the sealing line so as to define a predetermined region having one side of the sealing line as one side. Opening mechanism for heavy resin bags. 2. The opening mechanism according to claim 1, wherein the breaking line is formed in a triangular shape with a part of the sealing line as a base. 3. The opening mechanism according to claim 2, wherein a vertex of the triangular break line is formed in an arc shape. 4. The opening mechanism according to claim 2, wherein the apex angle of the triangular shape is 50 to 70 degrees. 5. The opening mechanism according to claim 1, wherein the breaking line has air permeability. 6. The line according to claim 1, wherein the break line is a perforation line.
The opening mechanism described. 7. The opening mechanism according to claim 6, wherein the perforated hole is a cut that is long in a cutting direction. 8. The opening mechanism according to claim 6, wherein the perforations are covered with a water-resistant coating that is easy to break. 9. A synthetic resin heavy bag provided with the opening mechanism according to claim 1, 2, 3, 4, 5, 6, 7, or 8.