JP2001206390A - bag - Google Patents

Abstract

(57) [Summary] [Problem] It can be manufactured with good productivity in the same process as a normal self-supporting bag, has good self-sustainability and air permeability, can efficiently store and transport after filling contents, Provide a bag with excellent display effect. SOLUTION: A bag 100 has a gusset portion 7 at a lower portion, that is, between a lower portion of a wall film 1 on both front and rear sides.
The bottom film is folded inward and inserted, and both sides and the lower edge are heat-sealed with the bottom seal part 3 to form a bottom part, and both side edges of the front and rear wall films 1 are side seal parts. At the time of forming the bottom by heat-sealing at 4 and 4 and forming the bottom, the bottom sealing portion is formed in the region including the lower portions on both sides of the bottom film folded into the gusset portion 7.
3 Notch on the bottom film that projects inward from
6 is provided so that the protruding portion forms the ventilation holes 10, 10. It is preferable to provide easy-opening means such as notches 8, 8 at the opening position of the bag 100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bag having a gusset at the bottom thereof, and more particularly, to a seal pattern for heat-sealing the gusset at the bottom of the bag, and a bag inserted inside the gusset. The present invention relates to a bag provided with self-sustainability and air permeability by adjusting the relationship of the shape of the bottom film cutout portions provided near the lower ends on both sides of the bottom film.

[0002]

2. Description of the Related Art Conventionally, a self-standing bag called a standing pouch is known as a bag having a gusset at the bottom. This self-supporting bag usually has
The bottom film is formed in a form with a gusset part that is formed by folding the bottom film inward and inserted between the lower parts of the laminated film on the front and rear wall surfaces. A notch is provided, and the gusset portion is heat-sealed with a seal pattern such as a ship bottom shape, and the body portion is formed by a side seal portion having a predetermined width on both side edges of the laminated film on both front and rear wall surfaces. It is formed by heat sealing.

[0003] In such a self-supporting bag, the contents are filled from the upper opening, so that the gusset portion at the bottom together with the trunk expands in a cylindrical shape, and at the bottom, the bottom seal portion of the ship bottom shape is used. At the same time, the lower edge portion of the gusset portion is heat-sealed, and the laminated films on both side walls are heat-sealed on both side portions thereof at the bottom film cutout portion. On the outer circumference,
A ring-shaped leg portion was formed by the heat sealing portion, thereby giving the bag self-supporting properties.

[0004] Such a self-supporting bag is easy to handle, can be packaged in a relatively compact size, and has an excellent display effect at stores. It is used for packaging products. In addition to the above-mentioned purpose of directly packaging the contents, it is also used for an outer bag for packaging the individually wrapped contents in units of 10, 20, 30, or the like. It is supposed to be.

[0005] An example of such an example is an outer bag that collectively packages sweeteners such as sugar and powdered milk for coffee that are packaged in sticks. When used as a bag, it is desirable that the bag is tightly packed with a small amount of air in the bag during storage and transportation after packaging, so that the appearance is good when displayed at stores. Therefore, it is desirable that air be introduced into the inside and that the air be in a plump form. In order to respond to such a demand, for example, means for providing a vent on the bottom surface of the self-supporting bag or the like is employed, and as a method of processing the vent, a method of punching out a small hole, or a method of forming various shapes is used. A method of providing a score line is employed.

[0006]

However, in the case of the method described above, the vent hole is provided by the method described above, since the small holes that are punched out are small, so that it is difficult to reliably remove the small holes and the holes may be mixed into the bag. There is also the bottom of the bag (ground surface)
If there is a small hole, there is a problem that foreign matter such as dust easily enters the bag. In addition, in the case of the method, there is a problem that it is difficult to obtain a sufficient ventilation effect unless the length of the score line is increased to some extent, and if the length is increased, the film tends to be torn from the end of the score line. Further, as a fundamental problem, in both cases, in order to provide the ventilation holes, it is necessary to add a ventilation hole processing step to the ordinary bag-making process, and there is a problem that the production cost is increased.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to improve the productivity in the same process as a normal self-supporting bag without increasing the number of processing steps. It has good self-sustainability and air permeability, is easy to handle, can be efficiently stored and transported after filling the contents, and has a display effect at stores. Another object is to provide excellent bags economically.

[0008]

The above objects can be attained by the present invention described below. That is, according to the invention described in claim 1, the bottom portion is formed in a form having a gusset portion formed by folding and inserting the bottom film inward between the lower portions of the front and rear wall films, and the peripheral edge portion is formed. In a self-supporting bag that is heat-sealed, a notch wider than the heat-sealing portion width of the peripheral edge of the bottom is formed in a region including the lower portions on both sides of the bottom film folded into the gusset portion of the bottom. The bag is characterized in that a part is provided. In the present invention, the heat seal is
It means to seal by thermal bonding, and the means are, in addition to sealing with a hot plate, impulse sealing,
Any of such as an ultrasonic seal may be used.

With this configuration, of the bottom film cutouts provided in the region including the lower portions on both sides of the bottom film folded into the lower portion of the bag, the edge around the bottom of the bag is formed. Since the portion that is wider than the heat seal portion and protrudes inward can be used as a vent, the size of the protruding portion, that is, the size of the vent can be freely adjusted within a range where the contents do not fall off. it can.

[0010] Therefore, the ventilation holes of any size can be provided only by changing the shape of the cutout portion of the bottom film, so that there is no need to increase the number of processing steps, and the production is performed in the same manufacturing process as a normal self-standing bag. It is possible to produce a bag that is excellent in air permeability as well as independence. Further, since the position where the air hole is formed is a position in contact with the inside of the heat seal portion around the bottom of the bag, the position is higher than the lower end of the bag, and the risk of foreign matter such as dust being mixed is reduced. Can be. In addition, the removal device itself is also provided with respect to the removal of the scraps from the cutout portion of the bottom film, and the size of the cutout portion is larger than in the past, so that the cutout can be more reliably removed. Therefore, it is possible to provide a bag having excellent independence and air permeability, easy to handle, efficient storage and transportation after filling the contents, and also excellent in display effect at the store with good economical efficiency. .

According to a second aspect of the present invention, there is provided the bag according to the first aspect, wherein the bottom gusset portion is heat-sealed with a ship bottom-shaped seal pattern.

The above-mentioned bottom seal pattern may be a bottom shape in which both sides rise in a curved shape from the center of the bottom, or a bottom shape having both sides rising in a straight line from the bottom having a fixed width and length. It may be in shape.

By adopting such a configuration, in addition to the function and effect of the invention described in the first aspect, the heat seal portion at the bottom of the bag gradually increases toward both sides, and the area of the heat seal portion is increased. At the same time, the rigidity of the film in the heat seal portion increases, so that the rigidity of the legs formed on the outer periphery of the bottom of the bag increases, and the self-sustainability of the bag can be further improved.

According to a third aspect of the present invention, there is provided the bag according to the first or second aspect, wherein an easy-opening means is provided at an opening position of the bag.

The above-mentioned easy-opening means includes (a) a method of providing a notch which is frequently used even in a normal bag, (b) a method of providing a half-cut line by laser light irradiation or the like;
A method of laminating an easily tearable film, for example, a uniaxially stretched film, in a laminated film of a bag (in this case, the uniaxially stretched film is easily oriented in a certain direction by using the stretching direction to coincide with the opening direction of the bag). (D) tears can be opened), (d) a method of forming elongated and small scars at the end of the bag by a mechanical method (the tears can be easily torn from the scars as a starting point), (e) cut tape There are various methods such as a method of sticking, and one of them can be selected or used in an appropriate combination.

As the notch, a one-shaped or V-shaped notch is often used, but the shape of the notch is not limited, and any shape may be used as long as it has a pointed portion in the tearing direction. The half-cut line is not limited to a continuous linear half-cut line, but may be an intermittent half-cut line such as a perforated line. Such a half-cut line may be one, but assuming that the tearing direction is shifted, a plurality of half-cut lines such as one each or two each on both sides of the center half-cut line, Alternatively, it can be provided in a shape converging with the center half-cut line.

By adopting such a configuration, in addition to the functions and effects of the invention described in claim 1 or 2, when opening the bag, tools such as scissors are not required and tearing can be easily performed only by hand. Can be opened.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a film used for a bag of the present invention and a method for producing the bag will be described. First, the film used for producing the bag of the present invention is not particularly limited, and a single film of a polyolefin-based resin such as polyethylene or polypropylene can be used as long as it has a heat-sealing property.
However, in order to improve the independence of the bag, it is preferable to use a film having high rigidity. In this regard, a laminated film in which at least a base material layer and a heat-adhesive resin layer (sealant layer) are laminated is used. Is preferred. When using such a laminated film, the rigidity of the outer substrate layer is high,
In addition, by using a film having excellent heat resistance, heat sealing can be performed at a high temperature, so that an advantage that productivity can be improved is also obtained. If it is desired to further increase the rigidity of the film, an intermediate layer can be further laminated between the base material layer and the heat-adhesive resin layer.

Representative examples of the structure of the laminated film that can be preferably used include the following structures. (Configuration of wall film) (1) PET film / extruded coat CPP layer (sealant layer) (2) PET film / PE layer for extruded laminate / C
PP film (sealant layer) (3) PET film / adhesive for dry lamination (hereinafter abbreviated as adhesive) / CPP film (sealant layer) (4) PET film / adhesive / OPP film / adhesive / CPP film (Sealant layer) (5) PET film / adhesive / uniaxially stretched PP film /
Adhesive / CPP film (sealant layer) (6) OPP film / extruded coat CPP layer (sealant layer) (7) OPP film / PE layer for extruded laminate / C
PP film (sealant layer) (8) OPP film / adhesive / CPP film (sealant layer) (9) PET film / extruded coat L / LDPE layer (sealant layer) (10) PET film / PE layer for extruded laminate / L
-LDPE film (sealant layer) (11) PET film / adhesive / L-LDPE film (sealant layer) (12) PET film / adhesive / OPP film / adhesive / L-LDPE film (sealant layer) (13) PET film / adhesive / uniaxially stretched PP film /
Adhesive / L·LDPE film (sealant layer) (14) OPP film / extruded coat L / LDPE layer (sealant layer) (15) OPP film / PE layer for extruded laminate / L
-LDPE film (sealant layer) (16) OPP film / adhesive / L-LDPE film (sealant layer), etc., but not limited thereto, various combinations of laminated films can be used. .

In the above structure, the PET film is a biaxially stretched polyethylene terephthalate film, the OPP film is a biaxially stretched polypropylene film, PP is polypropylene, CPP is unstretched polypropylene, PE is polyethylene, and L / LDPE is linear low density. It refers to polyethylene.

The outermost layer PET film or OPP film provides the bag with mechanical strength, rigidity, heat resistance and printability as a base layer, and the OPP film used for the intermediate layer is mainly used in this case. It is used to increase the thickness, rigidity and mechanical strength. Further, the uniaxially stretched PP film is laminated so that the stretching direction coincides with the tearing direction when the bag is opened, thereby facilitating the tearing and stabilizing the directionality.

As the sealant layer, CPP and L
-Although the example of the extrusion coat layer of LDPE or the non-stretched film was given, CPP has transparency, scratch resistance, heat resistance,
It is excellent in low odor and the like, and L-LDPE is excellent in heat seal stability, various contents resistance and the like. Therefore, it is preferable to use the bag appropriately depending on the use conditions of the bag, the type of the contents to be packed, and the like.

In addition to the above, an ethylene / α-olefin copolymer, ethylene / α-olefin
Vinyl acetate copolymer, ethylene / acrylic acid copolymer,
Ethylene / acrylate copolymers, ionomers, polyester resins, low-density to high-density polyethylene, and the like can also be appropriately selected and used.

In particular, an ethylene / α-olefin copolymer obtained by polymerization using a single-site catalyst such as a metallocene catalyst has a narrow molecular weight distribution and a stable copolymerization ratio. The sealant layer of the bag, which has excellent hot-sealing properties and has a difference in film overlap between the heat-sealed portions, such as the gusset portion and the upper portion thereof, such as the bag of the present invention, has a seal at the stepped portion. This is suitable in that pinholes can be prevented from being generated. Furthermore,
By using the copolymer blended with an olefin elastomer, the heat fluidity of the sealant layer is improved, and the occurrence of pinholes due to the steps can be more effectively prevented.

(Structure of Bottom Film) The bottom film is the same as the wall film except for the laminated film having a structure in which the uniaxially stretched PP film is laminated on the intermediate layer of (5) and (13). It can be preferably used.
However, as the thickness of the bottom film increases, as described above, there is a difference in film overlap between the gusset at the bottom of the bag and the portion above it, so the difference in thickness increases, and the side of the bag When heat sealing is performed, it is easy to cause a sealing failure at the boundary. Therefore, it is preferable that the thickness be smaller than that of the wall film, thereby stabilizing the heat sealing and at the same time obtaining the merit of reducing the packaging material cost.

Further, in the bag of the present invention, the vent is formed by a method in which the cutout portion of the bottom film is formed larger than that of a normal standing pouch, and the formed vent is torn by vibration or impact. In order to prevent the bottom film from becoming too large, it is preferable that the bottom film has particularly high tear strength. For this purpose, it is preferable to laminate a biaxially stretched nylon film (hereinafter referred to as ON film) on the bottom film. In addition to the above-mentioned constitution, for example, (1) ON film / extrusion coat CPP layer (sealant layer) ( 2) ON film / PE layer for extrusion lamination / CP
P film (sealant layer) (3) ON film / adhesive / CPP film (sealant layer) (4) ON film / extruded coat L / LDPE layer (sealant layer) (5) ON film / PE layer for extruded laminate / L・
LDPE film (sealant layer) (6) A bottom film having a constitution such as ON film / adhesive / L·LDPE film (sealant layer) can be suitably used.

Further, in the above arrangements (1) to (6),
A bottom film having a configuration in which a heat-adhesive resin such as PE is further laminated on the outside of the N film and sealant layers are provided on both sides can be used. However, in that case, when heat sealing the bottom part (gusset part) of the bag, a patch plate etc. is inserted between the gusset part front and rear pleats into other parts than both sides of the gusset part. The outer surfaces of the bottom films need to be heat-sealed so as not to be thermally bonded. Thereby, both sides of the gusseted part before and after the gusset part are heat-sealed by the sealant layers on the outside of the bottom film, so that the bottom film cutout portions provided at the lower parts on both sides of the bottom film become unnecessary. Therefore, it is only necessary to provide only the ventilation hole at a desired position of the bottom film by using a processing device for providing the bottom film notch.

Next, a method of manufacturing a bag of the present invention using the above-described laminated film will be described. As described above, the bag of the present invention is formed in such a manner that the bottom has a gusset portion formed by folding and inserting the bottom film inward between the lower portions of the front and rear wall films,
In a bag in which the peripheral edge is heat-sealed, a notch wider than the heat-sealed portion width of the peripheral edge of the bottom is formed in a region including the lower portions on both sides of the bottom film folded into the gusset at the bottom. By providing the portion, a vent hole is formed, and the bag is provided with self-sustainability and air permeability. It also includes a bag in which a gusset at the bottom of the bag is heat-sealed with a ship bottom-shaped seal pattern, and a bag provided with an easy-opening means at an opening position of the bag.

Such a bag is formed on the bottom (gusset portion) of the bag using a conventionally known standing pouch bag making machine (either a single-row bag making machine or a two-row butt bag making machine). By setting a seal pattern to a desired shape and preparing a seal head, and changing the shape of the bottom film cutout portion in accordance with this, bag making can be easily performed. In addition, when providing easy-opening means such as a notch and a half-cut line, a punching device corresponding to each, a laser beam irradiation device or the like is incorporated in the bag making machine, or by separately preparing, in-line with the bag making or It can be processed either offline.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below more specifically with reference to the drawings. However, the present invention is not limited to these drawings.

FIGS. 1 and 2 are front views showing the structure of an embodiment of the bag of the present invention. The bag 100 shown in FIG.
Is formed in a form having a gusset portion 7 in which the bottom film is inserted by folding the bottom film inward between the lower portions of the front and rear wall films 1, and both sides of the bottom film folded inward In this case, semicircular bottom film cutouts 6 and 6 are provided near the lower end, and both side portions and lower edge portions of the gusset portion 7 are heat-sealed by the bottom seal portion 3 having a predetermined width. Is formed. The bottom film cutouts 6 and 6 are provided in a shape that protrudes inward from the heat seal portion at the peripheral edge of the bottom, that is, the bottom seal 3, and the vent hole 10 is formed by the protruding portion. Is formed.

The body is formed by heat-sealing both side edges of the wall film 1 on both sides with side seals 4 and 4, and is formed in a bag shape with an open top. The upper seal portion 5 is an unsealed opening before filling the contents, and after filling the contents from this portion, heat sealing is performed. This is the same in the bag 200 shown in FIG. When the upper seal portion 5 is heat-sealed, a light deaeration seal may be performed in order to tightly package the contents. Is also good.

Notches 8, 8 are provided at the outer ends of the side seal portions 4, 4 near the lower side of the upper seal portion 5 as an easy-opening means for opening the bag. It is configured. The notch may be provided on only one side.
In addition, as the easy-opening means, in addition to the notch, a method of providing a half-cut line by laser light irradiation, a method of laminating a uniaxially stretched film on an intermediate layer of a laminated film on a wall surface, a method of attaching a cut tape There are various methods described above, and any of these may be provided alone or in combination as appropriate. In the bag of the present invention, although not shown in the drawing, inside the opening position,
Further, a zipper-type fastener that allows repeated resealing may be provided.

By adopting such a configuration, the bag 10
No. 0 can be manufactured with high productivity in the same process as a normal standing pouch, and the contents can be easily filled from the upper opening. And the bag 1 filled with the contents
00 indicates that the air in the bag is vented at the storage or transportation stage.
Since it can be pulled out of a tight form, the efficiency of storage and transportation can be improved, and when it is displayed at a store or the like, by introducing air into the bag through the vent hole 10, The bag 100 can be made plump, and the outer periphery of the bottom of the bag has a bottom seal portion 3.
As a result, a self-supporting property is provided, and the appearance, the display effect, and the like can be improved.

The bag 200 shown in FIG. 2 has the same configuration as the bag 100 shown in FIG. 1, except that the seal pattern of the bottom seal portion 3 for heat-sealing the bottom gusset portion 7 is formed by curving the inner line. In addition to changing to a ship bottom shape, in other words, a ship bottom shape seal pattern in which both sides rise in a curved shape from the center of the bottom,
As shown, the shape of the bottom film cutouts 6 on both sides is changed to a shape that includes the lower regions on both sides of the bottom film and protrudes from there into the bottom seal portion 3 of the ship bottom shape. , The protruding portions of which are vent holes 10,
10 are formed.

By adopting such a configuration, the bag 20
0 indicates that the bottom gusset 7 is heat-sealed with a ship bottom-shaped sealing pattern, and that the bottom gusset 7 is folded into the gusset 7 on both sides of the bottom film, including the lower part thereof. Since the bottom film notch portions 6, 6 having a shape protruding inward are provided, both sides of the gusset portion 7 are provided with the bottom film notch portions 6, 6.
The inner surfaces of the front and rear wall films 1 are heat-sealed at a portion where the bottom seal portion 3 of the ship bottom shape overlaps. Therefore, on the outer periphery of the bottom surface of the bag 200, a ring-shaped leg portion having rigidity is formed by the bottom seal portion 3 having a ship bottom shape, so that the self-sustainability is further improved, and the bottom film cutout portions 6 on both sides are formed. 6, the portion projecting inward from the bottom seal portion 3 forms the ventilation holes 10, 10, so that the bag 200 is provided with air permeability. Except for the above changes, the bag 200 has the same configuration as the bag 100 shown in FIG. 1. Therefore, the bag 200 has the same function and effect as the bag 100 shown in FIG. It works.

In the bag 200 shown in FIG. 2, the bottom seal pattern for heat sealing the lower gusset portion 7 is exemplified by the bottom seal pattern in which the inner line is formed by a curved line. For example, a ship bottom-shaped seal pattern in which both sides rise straight from the bottom with a fixed width and length with a slope on both sides outward.

[0038]

As described in detail above, claim 1 is as follows.
According to the invention described in the above, ventilation holes of any size can be formed by simply changing the shape of the bottom film cutout portion provided at the lower portion on both sides of the bottom film inserted by folding into the inside of the gusset portion at the bottom of the bag. Since it can be provided, it is not necessary to increase the number of processing steps, and it is possible to produce a bag excellent in productivity and air permeability as well as self-supporting in the same manufacturing process as a normal self-supporting bag. And the position where the ventilation hole is formed,
Because it is located in contact with the inside of the heat seal around the bottom of the bag, it is located higher than the lower end of the bag. Since the punching is performed in an integrated shape with the part, no small scraps of the ventilation holes are generated, and the scraps of the notch are removed by the scraper removal device for the bottom film notch already attached. It can be reliably removed. Therefore, the bag has excellent independence and air permeability, is easy to handle, can efficiently store and transport the contents after filling, and has an effect of economically providing bags excellent in display effect at stores. . According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, the heat seal portion at the bottom of the bag gradually increases toward both sides, and the area of the heat seal portion increases. At the same time, the rigidity of the film in the heat seal portion is high, so that the rigidity of the legs formed on the outer periphery of the bottom of the bag is increased, and the self-sustainability of the bag can be further improved. According to the invention described in claim 3, in addition to the operation and effect of the invention described in claim 1 or 2, since the easy-opening means as described above is provided at the opening position of the bag, When opening the bag, tools such as scissors are not required, and the bag can be easily torn and opened by hand alone.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration of an embodiment of a bag according to the present invention.

FIG. 2 is a front view showing the configuration of another embodiment of the bag of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wall film 2 Bottom part 3 Bottom seal part 4 Side seal part 5 Top seal part 6 Bottom film cutout part 7 Gusset part 8 Notch 9 Bottom film fold part 10 Vent hole 100, 200 bags

Claims (3)

[Claims] 1. A bottom portion is formed in a form having a gusset portion formed by folding a bottom film inside and inserted between lower portions of front and rear wall films, and a peripheral edge portion is heat-sealed. In the self-supporting bag, a notch portion wider than the width of the heat sealing portion at the peripheral edge of the bottom portion is provided in a region including the lower portions on both sides of the bottom film folded into the gusset portion at the bottom portion. A bag characterized by that: 2. The bag according to claim 1, wherein the gusset at the bottom is heat-sealed with a ship bottom-shaped seal pattern. 3. The bag according to claim 1, wherein an easy-opening means is provided at an opening position of the bag.