JP3766370B2 - paper bag - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper bag, and more particularly, the mouth portion is formed in a stepped manner with each end portion provided with a step in the length direction when viewed in a flat state, and sealing is provided on the stepped surface of the mouth portion. The present invention relates to a paper bag to which a hot melt adhesive is applied.
[0002]
[Prior art]
Conventionally, pinch bags are widely used internationally and are very well known. The structure of this pinch bag will be briefly described as follows. That is, the pinch bag is composed of a multilayered cylindrical body mainly made of kraft paper and formed by stepping at both ends, and the bottom of the multilayered cylindrical body bends the stepped surface at a predetermined position, for example, water-soluble It is closed by adhering to the outer wall surface of the multilayered cylindrical body with an adhesive or the like, and a hot melt adhesive is applied to the stepped surface of the mouth and cooled and solidified (for example, Patent Document 1). reference).
[0003]
Here, “step surface” refers to the end of the tubular body with pleats in a flat state (folded state), and all the edge edges of the plurality of layers forming the rear wall are the front wall. Each of the plurality of layers forming the portion is positioned so as to be shifted outward in the length direction of the cylindrical body, and each of the wall edge portions of each wall portion is also stepped in the length direction of the cylindrical body. The state where it has shifted. Such a pinch bag is excellent in leak-proof property, moisture-proof property, and the like, and also has excellent depositability (the overlapping state when pinch bags are stacked) because the mouth and bottom are symmetrical. Therefore, it has already been used for many years as the most excellent bag for transporting powders and granular materials.
[0004]
In a conventional pinch bag, when a hot melt adhesive is applied to the stepped surface of the mouth, the hot melt adhesive is applied using a roller type adhesive application device. However, when the hot melt adhesive applied to the stepped surface of the mouth is solidified, the mouth edges of the respective layers of the mouth are bonded to each other, and the virtual entrance into the paper bag is blocked. In order to prevent this, after applying the hot melt adhesive, the front and rear wall portions of the mouth portion are separated by means such as a rotary sucker to open the entrance. At that time, hot melt adhesive applied to the stepped surface of the mouth pulls the thread, and when it cools and solidifies, it easily breaks and falls into the paper bag, and then enters the contents filled in the paper bag, causing contamination problems. Could cause.
[0005]
That is, when the solidified hot melt adhesive thread is mixed into the contents, not only in the case of food packaging, but also in the case of packaging synthetic resin raw materials, films, plates manufactured from these synthetic resin raw materials, It may have a fatal effect on the quality of molded products. In order to solve such a problem, as described in Patent Document 1, on the stepped surface of the mouth, straddling the mouth edge of the paper bag defining the entrance into the paper bag in the longitudinal direction inward. It has been proposed to form a band-like area to which the hot melt adhesive is not applied over the entire width of the step surface.
[0006]
[Patent Document 1]
JP-A-2-26728 (left page of upper page 11th line to upper right page 3rd line, page 4 upper right page 3rd to 16th line, FIGS. 3 and 8)
[0007]
[Problems to be solved by the invention]
According to the pinch bag described in Patent Document 1, the hot melt adhesive is applied even after the front and rear wall portions of the mouth are separated after the hot melt adhesive is applied to the stepped surface of the mouth excluding the belt-like adhesive non-application area. However, there is no possibility of hot melt adhesive solidified into a thread form being mixed into the contents. However, in this pinch bag, after filling the contents in the pinch bag, the hot melt adhesive applied to the stepped surface of the mouth excluding the band-like adhesive non-application area is reactivated, and according to a conventional method Even when the mouth is closed, the hot melt adhesive does not spread over the entire width of the entrance into the paper bag (substantially open), so the content is like fine powder with high fluidity When an object is filled, there is a risk of leaking from the inlet, particularly from both sides of the inlet.
[0008]
The object of the present invention is to fill the contents such as fine powder having high fluidity without causing stringing of the hot melt adhesive applied to the stepped surface of the mouth due to such a conventional technical problem. It is to provide a paper bag that does not leak even in some cases.
[0009]
[Means for Solving the Problems]
The present invention relates to a paper bag formed by closing a bottom portion of a cylindrical body having a front wall portion and a rear wall portion facing each other, and the mouth portion of the paper bag is seen in a flat state, and the rear wall portion A mouth stepped surface formed by shifting the mouth end of the front wall portion from the mouth end of the front wall portion in the longitudinal direction of the paper bag, and an adhesive that is not coated with an adhesive on the mouth stepped surface. A non-application area and an adhesive application area coated with a hot-melt adhesive that surrounds the entire circumference of the adhesive non-application area are formed, and the adhesive non-application area is the mouth end of the front wall portion After filling the contents from the mouth portion, the stepped surface of the mouth is folded, and the hot melt adhesive in the adhesive application area of the stepped surface of the mouth before and after the folding is formed. It is reactivated and adhered to the front wall portion and sealed.
[0010]
Further, in the paper bag of the present invention, the cylindrical body may be formed from a plurality of layers, in which case the mouth step surface of the paper bag constitutes each mouth end of each wall portion. At least some of the edge edges of each of the layers are staggered in the longitudinal direction, and the adhesive non-application area provided on the stepped surface of the mouth constitutes the front wall. It is formed between two other mouth edge edges that straddle the mouth edge edge that is located on the outermost side in the length direction among the mouth edge edges of the respective layers to be adjacent to the mouth edge edge. It is characterized by.
[0011]
Furthermore, in the paper bag of the present invention, the cylindrical body is provided on both sides between the front wall portion and the rear wall portion, and can be folded in a lateral V shape inwardly between the front and rear wall portions. The adhesive may be formed with a pleated portion, in which case, the adhesive located between each side in the width direction of the adhesive non-application area and each side edge in the width direction of the stepped surface of the mouth. The width dimension of the application area is substantially equal to the folding depth dimension between the front and rear wall portions in the pleat portion when the mouth portion is viewed in a flat state.
[0012]
In the paper bag of the present invention, the cylindrical body may be formed of a cylindrical body without a pleat portion in which the side edge portions of the front wall portion and the rear wall portion are directly connected. The width dimension of the adhesive application region located between each side portion in the width direction of the adhesive non-application region and each side edge portion in the width direction of the stepped surface of the mouth, when the mouth portion is viewed in a flat state, It is approximately 3 to 5 cm from each side edge in the width direction of the stepped surface of the mouth.
[0013]
In the present invention, the paper bag can be constituted by the cylindrical body made of a single layer. Furthermore, in the present invention, the paper bag can be constituted by the cylindrical body composed of three layers of an outer layer, an intermediate layer, and an inner layer. Furthermore, in the present invention, when the cylindrical body is formed of a plurality of layers, the mouth portion of the cylindrical body of the inner layer constituting the paper bag is connected to each mouth that is not displaced in the longitudinal direction. It is also preferable to form by straight cutting consisting of edges. Further, in the paper bag of the present invention, in any case where the cylindrical body is composed of a pleated portion or not, or a plurality of layers or a single layer, the adhesive non-applied area is provided. The rectangular shape can be long in the width direction of the paper bag.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the embodiment shown in the drawings of the paper bag of the present invention will be described in more detail. FIG. 1 is a perspective view showing a pleated paper bag (hereinafter referred to as a paper bag) 1 according to a first embodiment of the present invention, and FIG. 2 is a longitudinal section of the paper bag 1 cut along line 2-2 in FIG. FIG. 2 is a configuration explanatory diagram schematically showing a structure. The paper bag 1 is provided with opposing front wall portion 2 and rear wall portion 3, and both side portions between the wall portions 2 and 3, and a pleat portion 4 that can be folded inwardly into a V shape. The bottom portion of the pleated tubular body having a fold is bent, and the bent portion is bonded to the outer wall surface with a water-soluble adhesive 14 and closed to form the bottom portion 5. In the paper bag 1 shown in FIGS. 1 and 2, the longitudinal direction refers to the direction indicated by the symbol “Y”.
[0015]
This paper bag 1 is formed by overlapping three pleated cylindrical bodies, and is therefore a three-layer paper bag in which each of the front wall portion 2, the rear wall portion 3 and the pleat portion 4 is composed of three layers. That is, in FIGS. 1 and 2, the front wall portion 2 is formed from the inner side of the paper bag 1 by the inner layer front wall surface 2 a, the intermediate layer front wall surface 2 b and the outer layer front wall surface 2 c, and the rear wall portion 3 is formed from the inner side of the paper bag 1. The rear wall surface 3a, the intermediate layer rear wall surface 3b, and the outer layer rear wall surface 3c are formed.
[0016]
The mouth portion 6 of the paper bag 1 is viewed in a flat state, and as a whole, the mouth end portion 8 of the rear wall portion 3 is shifted from the mouth end portion 7 of the front wall portion 2 to the outside in the length direction of the paper bag 1. It has the mouth step surface 9 formed. Further, in this embodiment, among the three pleated tubular bodies constituting the paper bag 1, the mouth end edges of the respective mouth portions are shifted stepwise in the longitudinal direction Y in the two pleated tubular bodies. .
[0017]
Specifically, each mouth edge 7b, 8b of the mouth portion in the pleated tubular body having the opposed intermediate layer front wall surface 2b and the intermediate layer rear wall surface 3b is formed in a stepped shape, and the opposed outer layer front wall surface Each mouth edge 7c, 8c of the mouth part in the tubular body with pleats having 2c and the outer layer rear wall surface 3c is formed in a step shape. In the pleated cylindrical body having the inner front wall surface 2a and the inner rear wall surface 3a facing each other, the mouth edges 7a and 8a, which are the mouth portions, are cut straight, that is, not displaced in the longitudinal direction Y. Is formed.
[0018]
However, as is apparent from FIGS. 1 and 2, when looking at the mouth edge 7a, 7b, 7c of each front wall surface 2a, 2b, 2c of the front wall portion 2, each of the mouth edges 7a, 7b, 7c is When the mouth edges 8a, 8b, 8c of the rear wall surfaces 3a, 3b, 3c of the rear wall 3 are arranged stepwise in the longitudinal direction Y, they are similarly displaced in the longitudinal direction Y. They are arranged in a staircase pattern. In addition, when the pleat portion 4 is also folded between the front and rear wall portions 2 and 3, the edge of the mouth is arranged stepwise in relation to the front and rear wall surfaces of each layer.
[0019]
In the stepped surface 9 of the mouth portion of the paper bag 1 formed in this way, the mouth edges 7a, 8a of the straight cut in the pleated tubular body having the opposed inner layer front and rear wall surfaces 2a, 3a are the facts into the paper bag 1. An upper inlet 15 is formed. The mouth stepped surface 9 is formed with an adhesive non-application area 10 where no adhesive is applied, and an adhesive application area 11 surrounding the adhesive non-application area 10 and applying an adhesive. Yes. The adhesive non-application area 10 is preferably a rectangular shape that is long in the width direction (direction perpendicular to the longitudinal direction Y) of the paper bag 1 as shown in the figure, but is not limited to such a rectangular shape. Absent. A hot-melt adhesive 12 is applied and dried and solidified in an adhesive application region 11 formed in an annular shape so as to surround the adhesive non-application region 10. A portion of the mouth portion 6 of the paper bag 1 shown in FIGS. 1 and 3 with a shadow line on the mouth step surface 6 is an application region 11 of the hot melt adhesive 12.
[0020]
The outer peripheral area edge of the adhesive application area 11 substantially coincides with the outer peripheral edge part of the stepped surface 6 of the mouth, but when the adhesive is actually applied, the marginal edge of the stepped surface 6 of the mouth is limited due to the application device. Since it is difficult to apply up to the surface, it is at a position slightly spaced from the peripheral edge of the mouth step surface 6 as shown in FIG. In particular, among the peripheral edges of the adhesive application area 11, the area edge 11a on the inner side in the longitudinal direction of the paper bag 1 is between the mouth edge 7c of the outer layer front wall surface 2c and the mouth edge 7b of the intermediate layer front wall surface 2b. It is best to be located at. However, the region edge 11a of the adhesive application region 11 is not limited to the position shown in FIG. In general, in the case of the paper bag 1 in which the mouth portion 6 is formed in a staircase shape, the position of the folding line 13 that bends the mouth portion 6 when the mouth portion 6 is closed by filling the contents is as shown in FIG. Furthermore, the paper bag 1 is scheduled slightly inward in the longitudinal direction from the mouth edge 7c of the outer layer front wall surface 2c. Therefore, the position of the region edge 11 a of the adhesive application region 11 may be set near the folding line 13.
[0021]
The rectangular adhesive non-application area 10 to which no adhesive is applied straddles the mouth edge 7a of the front wall surface 2a of the inner layer forming the virtual entrance 15 into the paper bag 1 in the longitudinal direction. It is formed between two other mouth end edges 7b and 8b adjacent to the end edge 7a. However, when the paper bag 1 is formed of a single-layered pleated cylindrical body having a front wall portion 2 and a rear wall portion 3 which are opposed to each other as shown in FIG. When the mouth edges of the plurality of front wall surfaces are not arranged stepwise, the rectangular shape provided across the mouth edge portion 7 of the front wall portion 2 in the longitudinal direction Y. Of the peripheral region edges in the adhesive non-application region 10, the region edge 10a on the inner side in the longitudinal direction of the paper bag 1 is closer to the outer side in the longitudinal direction than the region edge 11a of the adhesive application region 11 located in the vicinity of the folding line 13. It is preferable to be in the position.
[0022]
Of the peripheral region edges of the adhesive non-application region 10, the region edges 10b and 10c located on both sides in the width direction are folded between the front and rear wall portions 2 and 3 when the mouth portion 6 of the paper bag 1 is viewed in a flat state. The both folds 4 are located on the inner side in the width direction than the respective valley folds 4a. In other words, the width dimension S of the adhesive application area 11 located between the width direction edge 10b, 10c of the adhesive non-application area 10 and the width direction side edge of the mouth step surface 9 is the paper bag 1. When the mouth portion 6 is viewed in a flat state, the fold portion 4 is substantially equal to the folding depth dimension W between the front and rear wall portions 2 and 3.
[0023]
According to the paper bag 1 configured as described above, the stepped surface 9 of the mouth portion of the fold portion 4 straddling the folded end edge 7a forming the virtual entrance 15 into the paper bag 1 in the longitudinal direction and folded. A hot melt adhesive 12 is applied surrounding the adhesive non-application area 10 so as to form an adhesive non-application area 10 where no adhesive is applied, in a rectangular shape between the two valley folds 4a. The adhesive application area 11 prevents the entrance to the paper bag from being blocked by the adhesive after the hot melt adhesive is applied to the stepped surface of the mouth of the paper bag as in the conventional paper bag manufacturing process. Accordingly, the step of separating the mouth edge forming the inlet from the inner rear wall surface of the rear wall portion becomes unnecessary. As a result, no contamination occurs when the contents are filled, and the number of manufacturing processes can be reduced, so that productivity can be improved and thereby manufacturing costs can be reduced. .
[0024]
In the paper bag 1, a portion (range of the lateral dimension W) crossing the folded fold portion 4 in the mouth edge 7 a forming the actual entrance 15 into the paper bag 1 is a hot melt adhesive. It becomes a part of the cyclic | annular adhesive agent application area | region 11 to which the agent 12 is applied. If the hot melt adhesive 12 is applied to this portion, it is presumed that a question arises that the entrance of the paper bag 1 may not be opened when the contents are filled. However, when filling a paper bag 1 of this type with a content, a content filling device is almost used. In this apparatus, immediately before filling the contents, the front and rear wall portions 2 and 3 of the paper bag 1 are separated by means such as a rotary sucker, and the contents are filled after the entrance is opened.
[0025]
When forming the entrance of the paper bag 1 by separating the front and rear wall portions 2 and 3 of the paper bag 1 by means such as a rotary sucker in this content filling device, the vicinity of both side portions slightly below the mouth portion 6 of the paper bag 1 It is necessary to hold down firmly. For this reason, the content filling device is usually provided with a gripping clip portion for supporting the paper bag 1 by sandwiching both side portions of the mouth portion 6 of the paper bag 1 from the outer surface side of the front and rear wall portions. Each gripping clip portion is constituted by a pair of chucks (grip plates), and the gripping allowance dimension of the chuck is substantially the same as the folding depth W of the fold portion.
[0026]
Therefore, when the contents are filled in the paper bag 1, the both sides of the paper bag 1 are sandwiched from the outer surface side of the front and rear wall portions by the same width dimension W as the folded pleat portion 4 with each chuck of the content filling device. Since the paper bag 1 is supported, the pleat 4 of the mouth 6 is not opened. Therefore, even if the pleat 4 of the mouth portion 6 does not open with a hot melt adhesive pre-applied to this part, there is no hindrance to the filling of the contents, but rather by applying an adhesive to this part, Even if the content filled in the paper bag 1 is a fine powder having high fluidity, it is possible to obtain an effect that leakage from both sides of the mouth can be surely prevented.
[0027]
The method for closing the mouth portion 6 in the paper bag 1 is exactly the same as the conventional method, and the hot-melt adhesive of the adhesive application area 11 that is applied annularly to the mouth step surface 9 after the contents are filled. Hot air is blown onto the agent 12 to reactivate it, the mouth part 6 is bent along the folding line 12, and the outer layer wall surface 2c is overlaid and bonded, and the mouth part 6 is closed.
[0028]
In the paper bag 1 of the first embodiment described above, the case where the paper bag 1 is formed from a single-layered or multi-layered pleated cylindrical body is taken as an example, but the present invention is limited to such an embodiment. Instead, even in the case of the pleated paper bag 16 formed of a cylindrical body in which the side edges of the front and rear wall portions 2 and 3 are directly connected to each other as in the second embodiment shown in FIG. The same can be applied. In the pleated paper bag 16 shown in FIG. 6, the same or corresponding components as those in the pleated paper bag 1 of the first embodiment shown in FIGS. To do. The pleated paper bag 16 shown in FIG. 6 is formed of three layers, but can also be formed of a single layer.
[0029]
In the case of the pleated paper bag 16, the adhesive application area 11 positioned between the width direction area edges 10 b and 10 c of the adhesive non-application area 10 and the width direction side edges of the mouth step surface 9. The width dimension S is about 3 to 5 cm, preferably about 3 cm. This is somewhat different depending on the manufacturer, but the grip allowance of the pair of chucks (grip plates) constituting the grip clip portion of the content filling device is about 3 to 5 cm, and the pleated paper bag 1 Are also approximately the same size as the folding depth W of the average pleat 4 so that they can be used in common.
[0030]
Even in the case of the pleated paper bag 16, when filling the contents, the paper bag 16 is supported by sandwiching the width of about 3 to 5 cm on both sides in the vicinity of the mouth portion 6 of the paper bag 16 by the chuck of the content filling device. Therefore, even if a hot melt adhesive is applied in the range of the width dimension sandwiched by the chuck, there is no hindrance to the filling of the contents, but rather the paper bag 16 is filled by applying the adhesive to this part. Even if the content to be processed is like a fine powder having high fluidity, it is possible to obtain an effect that leakage from both sides of the mouth portion 6 can be surely prevented.
[0031]
In the paper bag 1 of the above-described embodiment, the bottom portion 5 is formed by folding the bottom end of the pleated tubular body and closing the bent portion by adhering it to the outer wall surface with a water-soluble adhesive 14 or the like. However, since the bottom structure is not the gist of the present invention, it may have any structure.
[0032]
【The invention's effect】
As described above, according to the paper bag of the present invention, when the hot melt adhesive is applied to the stepped surface of the mouth, the entrance of the paper bag is not closed with the adhesive, and is bonded by the conventional paper bag manufacturer. In order to prevent the inlet from being closed by the agent, the process of solidifying the adhesive with the paper bag inlet open in advance is unnecessary, which can improve the productivity and reduce the cost of the paper bag, and it has a high fluidity. Even when the mouth is closed according to a standard method after filling the contents such as powder, the contents do not leak from both sides of the mouth closing part.
[Brief description of the drawings]
FIG. 1 is a perspective view of a pleated paper bag according to a first embodiment of the present invention.
FIG. 2 is a structural explanatory view schematically showing a layer structure of a pleated paper bag cut along line 2-2 in FIG. 1;
FIG. 3 is a partial plan view showing the mouth portion of the pleated paper bag of FIG. 1 in a flat state.
4 is a plan view showing a partially enlarged mouth portion of the pleated paper bag shown in FIG. 3. FIG.
FIG. 5 is a plan view similar to FIG. 4, partially enlarged showing a mouth portion of a pleated paper bag according to a second embodiment of the present invention configured from a single-layer pleated tubular body.
FIG. 6 is a plan view showing a paper bag according to a third embodiment of the present invention configured from a single-layered pleated cylinder.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Paper bag with fold 2 Front wall part 2a Inner layer front wall surface 2b Middle layer front wall surface 2c Outer layer front wall surface 3 Rear wall part 3a Inner layer rear wall surface 3b Middle layer rear wall surface 3c Outer layer rear wall surface 4 Fold part 4a Valley fold part 5 Bottom closing part 6 Mouth portion 7 Mouth end portion 8 of front wall portion Mouth end portion 9 of rear wall portion Stepped surface 10 of mouth portion Adhesive non-application area 10a Area edges 10b and 10c on the inner side in the longitudinal direction of the adhesive non-application area Area border 11 in width direction of application area Adhesive application area 12 Hot melt adhesive 13 Folding curve 14 Water-soluble adhesive 15 Entrance 16 into paper bag Paper bag without pleats

Claims (8)

In a paper bag formed by closing the bottom of a cylindrical body having a front wall portion and a rear wall portion facing each other,
The mouth portion of the paper bag is viewed in a flat state, and the mouth stepped surface formed by shifting the mouth end portion of the rear wall portion from the mouth end portion of the front wall portion to the outside in the longitudinal direction of the paper bag. And an adhesive non-application area where no adhesive is applied and an adhesive application area where a hot-melt adhesive that surrounds the entire circumference of the adhesive non-application area is applied to the stepped surface of the mouth. Formed, the adhesive non-application area is formed across the mouth end of the front wall,
After filling the contents from the mouth portion, the stepped surface of the mouth is folded, and before and after the folding, the hot melt adhesive in the adhesive application area of the stepped surface of the mouth is reactivated and the front wall A paper bag that is adhered and sealed to a part. The cylindrical body is formed of a plurality of layers, and the stepped surface of the mouth of the paper bag includes at least some of the mouth edges of the layers constituting the mouth ends of the walls. , Formed in a stepped manner in the longitudinal direction,
The adhesive non-application area provided on the stepped surface of the mouth straddles the mouth edge located on the outermost side in the length direction among the mouth edges of the layers constituting the front wall portion. The paper bag according to claim 1, wherein the paper bag is formed between two other mouth edge edges adjacent to the mouth edge edge. The cylindrical body includes pleat portions provided on both sides between the front wall portion and the rear wall portion and foldable in a lateral V shape inwardly between the front and rear wall portions, The width dimension of the adhesive application region located between each side in the width direction of the non-application area and each side edge in the width direction of the stepped surface of the mouth is the pleat when the mouth is viewed in a flat state. The paper bag according to claim 1, wherein the paper bag is substantially equal to a folding depth dimension between the front and rear wall portions in a portion. The cylindrical body is formed of a cylindrical body without a pleat portion that directly connects the side edge portions of the front wall portion and the rear wall portion, and each side portion in the width direction of the adhesive non-application area; The width dimension of the adhesive application area located between each side edge in the width direction of the mouth step surface is such that each side edge in the width direction of the mouth step surface when the mouth is viewed in a flat state. The paper bag according to claim 1, wherein the paper bag is approximately 3 to 5 cm from the portion. The paper bag according to any one of claims 1, 3, and 4, wherein the paper bag is composed of the cylindrical body made of a single layer. The said paper bag is comprised from the said cylindrical body which consists of three layers, an outer layer, an intermediate | middle layer, and an inner layer, The paper bag in any one of Claims 2-5 characterized by the above-mentioned. The mouth portion of the cylindrical body of the inner layer constituting the paper bag is formed by straight cutting made up of each mouth edge that is not displaced in the longitudinal direction. 6. A paper bag with pleats according to any one of 6 above. The paper bag according to any one of claims 1 to 7, wherein the adhesive non-application area has a rectangular shape that is long in a width direction of the paper bag.

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