JP2992439B2 - Bottom folding bag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an bottom folding beams bag, when handling this by filling the contents into the interior of the bag is more, wraparound of the contents in the closed portion of the bag mouth and bottom sides the small comb relates bottom folding Beams bag to prevent leakage and spillage.

[0002]

2. Description of the Related Art Recently, a paper bag formed of a material mainly made of kraft paper has been used in the form of a tubular body having straight ends cut at both ends for ease of manufacture and the like. The end of the cylindrical body is bent so that the contents can be taken out, and the bent part is surrounded and fixed with a piece of paper and closed.

The structure of a conventional general paper bag in which the bottom closure is to be opened in the future will be described in more detail. This type of paper bag is mainly composed of a cylindrical body having straight cut ends. I have. A V-shaped cross section is formed on both sides of the tubular body, and one end thereof is bent at least one time, and a backing sheet is disposed across the bent section. It was adhered to each wall of the tubular body. As a result, the bent portion was surrounded and fixed by the backing paper, and thus was a bottom closed portion. A paper bag provided with a bottom closure configured in this way is generally called a bottom fold bag.

[0004] At the bottom closing portion of the bottom folding bag,
An opening tape is affixed to the inner surface of the backing sheet surrounding and fixing the bent portion so that the contents can be easily opened when the contents are taken out, and the backing sheet has a cut as a handle. Therefore, at the time of opening, the contents can be taken out from the bottom side of the tubular body by pulling up the opening tape, tearing off the backing sheet, and returning the folded portion to its original position.

[0005]

However, there is a conventional method in which the end of the cylindrical body is bent, and the bent portion is surrounded and fixed by a backing paper to close it. In a bottom-folded bag, when a powdery or granular material is filled as a content, when opening, in other words, when the end of the folded cylindrical body is returned to its original shape, the cylindrical shape whose content was bent There has been a problem that a small amount of water is spilled from the opening at the end of the body.

[0006] It has been thought that such a type of leakage does not occur in all bags of this type, and therefore may be due to differences in handling. However, the occurrence of such leakage from the opening at the time of opening does not basically cause any problem with the performance of the paper bag itself. However, such leakage is nothing but hopeless.

By the way, before such a paper bag formed of a cylindrical body having both ends formed by straight cuts, a paper bag called a pinch bag formed of a cylindrical body formed by steps cut at both ends was used. Widely used. As disclosed in Japanese Patent Publication No. 39-28726, this pinch back is formed by bending a stepped one end of a tubular body and firmly bonding the flap to a wall surface with an adhesive to form a closed bottom. It is. Therefore, the configuration is fundamentally different from that of the above-described bottom-folding bag in which the tubular body having the straight cut end is bent so that it can be easily opened in the future.

[0008] In such a pinch bag, in a tubular body having both ends stepped in a stage before completion as the bag, the flaps at both ends are formed in opposite directions. The reason that the direction of the closing flap connected from the wall in this way is opposite in the cylindrical body with both ends stepped is usually such a cylindrical body formed by cutting a long sheet continuously stepwise. And is well known.

The inventor of the present invention has proposed that the tubular body having such a straight cut end be folded and closed for a long time to open the bottom folded bag having a bottom closed portion which can be opened in the future. As a result of continuing research on the problem of spills from the department, I have recently noticed a crucial fact. It is the relationship between the direction of bending the end portion of this type of paper bag and the handling state of this paper bag. In other words, the relationship between the two is leakproof and
It is said to be a very large cause of the spillage of the contents.

[0010] In view of the above, an object of the present invention is to provide a bottom folding bag having a bottom closing portion which bends the ends of the straight-cut cylindrical body at both ends, surrounds and fixes the end with a backing sheet, and can be opened in the future. Leakage of contents in closed mouth
It is another object of the present invention to provide a bottom folding bag which solves the problem of how to prevent the spilling from the end opening when the contents are taken out by opening the bottom closure .

[0011]

SUMMARY OF THE INVENTION According to the present invention, there is provided a bottom folding bag formed with a body sticking portion formed by sticking both side edges of kraft paper , and the side where the body sticking portion is located is defined as a back surface, a cylindrical body at both ends straight cutting in which the side facing to the back side surface, folding <br/> bent twice one end of the tubular member to the surface side, surrounded fixed paper against the bent portion is formed Te,
Construct a bottom closure that will be opened in the future and this bottom closure
Extending in the width direction of the backing paper to be provided on the inner surface thereof
When the backing sheet surrounds and bends the bent portion
Opened to be located on the surface side of the cylindrical body
Tape and the bottom folded bag at the other end of the tubular body
When the end is bent toward the front side after filling the contents from the contents filling port, the filling port side affixed in advance to the back surface of the other end so that the bent portion can be surrounded and fixed. Paper and the tube as a filling port of the contents of the bottom folding bag
After bending the other end of the body, surround the bent portion
Coated on the backing paper so that it can be attached to the surface of the cylindrical body
Is composed of a adhesive, when the filling opening is folded closed content is filled into the bottom folding beams bag, the
A bent portion at each end of the tubular body is configured to be bent toward the front surface side.

Further, the bottom folded bag of the present invention is as described above.
Adhesive means is applied to at least the folded side of the backing paper
Characterized in that it is a hot-melt adhesive that has been used .

[0013]

According to the bottom-folding bag of the present invention, the contents of the bag are filled with powdery or granular materials as contents from the mouth of the bag. The sheet is bent once, and the adhesive applied to the portion protruding from the end of the mouth is reactivated to adhere to the surface of the bag on the bent side with the adhesive.

In such a bottom folded bag, the surface on which the body sticking portion is located is usually the back side, that is, the back surface, and the opposite side is the front surface, that is, the front surface. Therefore, various indications concerning the contents are printed on this surface, and in the distribution of the paper bag after filling the contents, transportation and laying are almost always performed with reference to this surface on which the main printing has been performed. It has been treated to be.

However, in the bottom folding bag of the present invention, the end of the cylindrical body constituting the bottom closing portion is bent to the bag surface side where the body sticking portion is not formed, and is fixed and closed with the backing paper. Because of this, the contents are less likely to enter this upward-facing bend while handling such as transporting or accumulating,
As a result, there is no danger of the contents spilling out of the mouth end when opening and removing the bottom closure.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a folding bag according to the present invention. FIG. 1 shows a flattened bottom sack 10 according to one embodiment of the present invention. This bottom fold bag 10 is 84 g / m ^2.
The two side edges of two pieces of kraft paper are attached to each other to form a body sticking portion 11, and the body sticking portion 11 is flattened so as to be located on one wall surface and has a single-layer cylindrical shape having a gusset 12 on both sides. It is composed of a body 13.

The cylindrical body 13 is a so-called straight cut end in which both ends are cut straight. This cylindrical body 13
The gussets 12 formed on both sides of the valley are flattened at the middle part of the valley along the longitudinal direction when flattened to form a V-shaped cross section. As shown in FIGS. 1 and 2, the bottom folded bag 10 has one end of the cylindrical body 13 and a wall opposite to the one wall on which the body sticking portion 11 is present (hereinafter simply referred to as a surface 14 a).
The wall surface on which the body sticking portion 11 is present is referred to as a back surface 14b), and is folded twice to cover the bent portion 15 so as to surround the front surface 14a and the back surface 14b of the tubular body 13. 16 attached to both sides to form a bottom closure 1
7 is provided.

An opening tape 18 extending in the width direction is adhered to the inside of the backing paper 16 constituting the bottom closing portion 17. As can be seen from FIG. 2, the opening tape 18 is provided at one end of the cylindrical body 13 at the bent side, that is, at the surface 1.
It is provided so as to be located on the 4a side.

On the other hand, the mouth of the bottom foldable bag 10, that is, the other end of the cylindrical body 13, is connected to the bottom closing portion 1 after the contents are filled.
When the end is bent at the bending line 19 on the front surface 14a side in the same manner as in 7, the rear surface 14b of the tubular body 13 projects from the mouth side edge so as to surround and bend the bent portion. And a backing paper 21 having only an end bonded with an adhesive 20. Then, as shown in FIGS. 3 and 4, a portion 21 a of the backing sheet 21 protruding from the mouth of the tubular body is connected to the tubular body 1.
An adhesive 22 such as a hot melt, which is reactivated by heat, is applied over the mouth end of No. 3.

The adhesive 22 is provided to close the opening on the side of the filling opening when the contents are filled in the folded bottom bag 10. As shown in FIGS. 5 and 6, the adhesive 22 provided for such a purpose does not apply to the end of the mouth of the tubular body 13 but protrudes from the mouth of the tubular body 21 of the backing paper 21. It may be applied over the portion facing the back side of the mouth end of the cylindrical body 21a and the continuous portion thereof.

The method of using the bottom foldable bag 10 constructed as described above will be described. After filling the powdery or granular material from the mouth, the end of the mouth is folded along the folding line 19 together with the backing paper 21. Bending, then the protruding part 21 of the backing paper 21
The adhesive 22 applied to the a and the end of the cylindrical body is heated and reactivated by hot air or the like, and then is adhered to the surface 14a and closed to form a mouth closing portion 23.

As a result, the closed mouth end filled with the contents is exactly the same as the square bottom closed portion 17 as shown in FIG. Is different). That is, the mouth closing portion 23 of the bottom folding bag 10 has the bottom closing portion 17.
The bent portion faces the surface 14a in the same manner as in the first embodiment.

In short, the bottom folding bag 10 is similar to that shown in FIG.
As clearly shown in the figure, the bending direction in which one end of the tubular body 13 is bent to form the bottom closing portion 17 is the same as the bending side in which the contents are inserted through the mouth and then the mouth end is bent. And both are bent to the same surface 14a side.

As described above, particularly when the end of the cylindrical body 13 is bent toward the front side at the bottom closing portion 17 to close the opening, the opening at the time of returning the bent portion 15 to its original state at the time of leakage of contents, ie, opening. Almost no spillage occurs.
The reason will be described in detail below. Generally, this type of bottom foldable bag has a body sticking portion as indicated by reference numeral 11 in the above-described embodiment, and the surface where the body sticking portion is located is usually the back side, that is, the back surface 14b, and the opposite side is the face side, ie, the front side. It becomes the surface 14a.

Therefore, various indications concerning the contents are printed on this surface 14a, and in the distribution of the bottom folding bag after the contents are filled, the transportation and the laying are performed mainly on the surface 14a on which the main printing is performed. As a reference, always this surface 1
4a is handled upward. However, conventionally, the end of the tubular body 13 has been appropriately bent without considering the handling state of the bottom folded bag at all.

That is, the bottom folded bag made of the cylindrical body having the straight cut end can be structurally bent in either direction, and the bending direction has a special arrangement. As described above, if the end of the tubular body is bent toward the back surface 14b of the bottom closing portion 17 as described above, the end of the mouth closing portion 23 is bent toward the front surface 14a, or the bottom closing portion 17 has a cylindrical shape. If the body end is bent toward the front surface 14a, the back 14
Bending in the direction opposite to each other as described above.

In some cases, the reason that the front surface is made wide in consideration of the appearance of the bottom folded bag is that, for example, the flap bending direction of the end portion, such as an envelope or a paper bag for storing letters and documents, is the same as that of the back side with the body sticking portion. In view of the opinion that it is preferable to do so, as shown in FIG. 8, there has been a case where a method is employed in which both the bottom closed portion and the mouth closed portion have their ends bent toward the back surface 14b as shown in FIG. In short, I never thought about folding in relation to the front and back of the bag.

Now, as shown in FIG. 8, the bottom of the cylindrical body 13 is bent toward the back surface 14b (the bag is denoted by reference numeral 30 and its bottom closing part and mouth part). (The closed portions are indicated by reference numerals 31 and 32, respectively)), and the results of an analysis of what acting force is applied to the bent portion during handling of the bag 30 will be introduced.

Now, the first folded portion of the double folded portion 33 in the bottom closing portion 31 is a first folded portion 33a, and the second folded portion is a second folded portion 33b.
And As the contents are filled and the filling port is described above,
The closed bottom fold bag 30 is usually mainly composed of the surface 14a.
It is transported on a pallet with a number of them facing up, and it is unlikely that it will be turned upside down.

Therefore, as shown in FIG. 9, the bent portions 3 in the closed bottom portion 31 from the inside of the bottom folded bag 30.
Looking at 3, the passage 34b (passage to the mouth) of the second folded portion 33b, which is closed by bending, is directed downward. As a result, the contents 35 are moved downward by the second folded portion 33b due to vibrations received during transportation of the bag.
As shown in FIG. 10, the vehicle enters the inside passage 34b. Then, a part of the material is pushed into the first folded portion 33a so as to be pushed out by the further entering pressure applied to the contents 35 having entered the second folded portion 33b.

In order to open the bottom folded bag 30 in such a state, the bag 3
0, and when the backing sheet 16 is torn and the folded portion 33 is to be returned to the original position, as shown in FIG.
Since the mouth end of 3a faces downward, the contents 35 that have wrapped around the passage 34a of the first folded portion 33a will spill from the mouth end.

However, the bent portion 15 constituting at least the bottom closed portion 17 like the bottom folded bag 10 of the present embodiment.
The surface 14a of the cylindrical body 13 on which the body sticking portion is not formed
When folded to the side, as described above, the bag 10 is always handled with this surface 14a facing up, so that the passage of the second folded portion 15b faces upward, so that the contents are less likely to enter the second folded portion 15b. (Reduced to 1/5 as compared to the bag of FIG. 8), and as a result, it was found that there was almost no content entering the first folded portion 15a.

Therefore, in the case of the folded bottom bag 10 of this embodiment, when the bottom closing portion 17 is opened and the end bent portion 15 of the cylindrical body 13 is returned to the original state to take out the contents,
No spilling of content from the mouth end.

[0034] In order to confirm why there is a difference in the manner of folding, the contents were cut and the end was cut to examine the state of bending. When the contents were loaded and handled, the bag was folded to the front side of the bag. In this case, the bent portion was not opened as shown in FIG. 7 and the original shape was maintained. On the other hand, when the bend is downward, as shown in FIG.
4b was found to open. As a matter of course, in order for the contents to enter the passage 34b, FIG.
In the case of (1), the contents must be lifted from the bottom up, but it is expected that the part is pressed against the bent portion by the contents, so that difficulty is expected. On the other hand, in FIG. 8, it is considered that the content easily flows from top to bottom, and the bent portion is easily opened around the end.

[0035] While the embodiment has been described a paper bag with a bottom closure portion serving as a future opening port, content filling port side i.e.
The mouth of the bag is closed by bending the end once. this
In this case, the rotation of the contents at the mouth closure
As in the case of the chain portion, it changes in front and back folds. In the case of front and back folds, the danger of leakage of contents is extremely small, but in the opposite direction (
Folding increases the risk of leakage .

The results confirmed by actual experiments are shown below. (Test results) The test bag was made of 84 g / m ² kraft paper to form a two-layer structure, and the dimensions were 813 × 455 × 1.
At 15 mm, the content filling port was bent once, and the content was filled with 25 kg of polypropylene. Hold the mouth closed part and the bottom closed part with both hands, place the bottom folded bag horizontally with the surface facing up, and drop it from a height of 50 cm.
The bottom closing part was opened each time, twice in succession, and five times in succession, and the amount of resin flowing to the second folded part was measured in grams. Table 1 shows the results.

[0037]

[Table 1]

As is clear from Table 1 above, in the configuration of the closed bottom portion, the amount of rotation when the end of the tubular body is bent to the back side (reverse folding) is the case when the end is bent to the front side (front side). 6.56 times for the bottom folded bag in the case of one drop, 3.80 times in the case of two times,
It was 5.81 times in the case of five times, and it was confirmed that the amount of rotation was remarkably smaller in the case of the front folding.

[0039]

As described above, according to the bottom folded bag of the present invention, (1) the both side edges of the kraft paper are stuck together.
One end of a cylindrical body cut straight at both ends with
Front side opposite to the side where the body sticking part is located (back side)
(2) Open this bent part
Bottom part that can be opened in the future by surrounding and fixing with a paper with a loop
This opening tape is positioned on the front side of the
It is provided to be placed.

Further, (3) a cylinder which is a content filling port
The other end of the body also closes its filling port after filling the contents
Inevitably, bend it to the surface side opposite to the
Wrapped around with paper. Three like this
Combined with the elements of this, the user of this bottom folding bag, kana
Handle the folded bag with its surface up.
Around the contents into the fold that constitutes the bottom closure
The contents are open when opened.
This can significantly reduce spills,
Can prevent surrounding contamination,
From the mouth closure that was folded and closed after filling the contents
Can be prevented from leaking.

[Brief description of the drawings]

FIG. 1 is a plan view showing a flattened bottom folding bag according to an embodiment of the present invention.

FIG. 2 shows a bottom folded bag of the embodiment shown in FIG.
It is sectional drawing which cut | disconnects along a line and shows schematically.

FIG. 3 is a front view partially showing a content filling port in the bottom folding bag of the embodiment shown in FIG. 1;

FIG. 4 is a cross-sectional view of the bottom filling bag of the present embodiment shown in FIG.

FIG. 5 is a partial front view similar to FIG. 3, showing another modified example of the content filling port in the bottom folding bag of the present invention.

FIG. 6 is a partial cross-sectional view showing the content-filled side of the bottom-folded bag shown in FIG. 5 along the line 6-6.

FIG. 7 is a cross-sectional view showing a state in which the bottom folding bag according to the embodiment of the present invention shown in FIG.

FIG. 8 is a cross-sectional view showing a state in which both ends of the tubular body are bent toward the back surface side where the body sticking portion of the tubular body is located, and the contents are turned to the bent portion in a state where each is closed.

FIG. 9 is a view of the bottom closed portion viewed from the inside of the bag when one end of the cylindrical body is bent so as to be opened in the future and the contents are put into a bottom folding bag having a bottom closed portion and formed into a square shape. FIG.

FIG. 10 is a cross-sectional view showing a state in which the contents are wrapped around the bent portion in the bottom folding bag shown in FIG. 8 in which an end portion of the tubular body is bent to the back side to form a bottom closed portion.

FIG. 11 is a partial cross-sectional view schematically showing a state in which the bottom folding bag shown in FIG.

FIG. 12 is a partial cross-sectional view schematically showing a state in which the bent portion, which is the bottom closed portion, is returned to the original state for opening in the bottom folding bag shown in FIG. 11, together with a wraparound state of the internal contents. is there.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Bottom folding bag 11 Body sticking part 12 Town 13 Cylindrical body 14a Front surface 14b Back surface 15 Folding part 16 Backing paper 17 Bottom closing part 18 Opening tape 19 Contents filling side bending line 20 Adhesive 21 Contents filling opening side Backing paper 21a Protruding part of backing paper 22 Hot melt adhesive 23 Contents filling port side closing part 30 Bottom folding bag 31 Bottom closing part 32 Mouth closing part 33 Bending part 33a First folding part 33b Second folding part 34a passage 34b passage

Claims (1)

(57) [Claims] 1. A bottom folding bag formed with a body sticking part in which both side edges of kraft paper are stuck together, a side where the body sticking part is located is a back surface, and a side facing the back surface is a front side. a cylindrical body at both ends straight cut that was bent twice at one end of the tubular member to the surface side, is formed to surround fixed paper against the bent portion, it future opening
Extending in the width direction of the backing sheet constituting the bottom closing part,
And the backing paper is provided on the inner surface of the
Is located on the surface side of the cylindrical body when the surrounding portion is fixed around
And the filling of the contents of the bottom folding bag which is the other end of the tubular body
After filling the contents from the mouth , fold this end to the front side
When bent, a filling port side backing sheet previously attached to the back surface of the other end so as to surround and fix the bent portion, and the cylindrical body serving as a content filling port of the bottom folded bag. Other
After bending the end, the cylindrical shape is used to surround the bent portion.
Adhesion applied to the backing paper so that it can be attached to the surface of the body
The bottom folding bag is filled with contents and the filling port is folded.
When bent and closed , each bent portion at each end of the cylindrical body is configured to be bent toward the front surface side.
Bottom folding beams bag, characterized in that there.