JPWO2017099249A1 - Flexible container - Google Patents

Abstract

[PROBLEMS] To provide a flexible container that solves the problems of filling efficiency and filling shape and enables stable stacking. A flexible container according to the present invention includes an inner bag made of at least one layer of plastic film having a deaeration mechanism, and a breathable outer bag having a body portion, an upper surface, and a lower surface, and in which the inner bag is built. It is characterized by comprising. The degassing mechanism is capable of degassing the air remaining in the inner bag after the filling of the flexible container of the present invention through the inner bag without the leakage of the packing and the entry of foreign matter from the outside. Any mechanism and structure can be used without particular limitation. As a suitable deaeration mechanism, for example, a plurality of deaeration hole groups penetratingly installed inside and outside the inner bag, in particular, micro perforation hole groups, are preferably used. When using a deaeration hole group as a deaeration mechanism, the said deaeration hole group can be provided in the whole surface or a partial area | region of the said inner bag. [Selection] Figure 1

Description

  The present invention relates to a flexible container used for transporting and storing powder and the like, and more specifically, by degassing the air in the inner bag during stacking, so that two or three stages are stably provided. The present invention relates to a flexible container that can be stacked upward.

  Currently, in a wide range of industries, flexible containers are used to transport and store various substances, such as resin pellets, chemical products, inorganic substances, minerals, grains, feeds, etc. It is used. The flexible container basically includes a cylindrical body, an upper surface and a lower surface sewn to the upper and lower edges of the body, and a suspension belt attached to the body. The trunk portion includes a sealing portion that can be sealed in the central region of the upper surface thereof, and a discharge portion that can be sealed in the central region of the lower surface as necessary.

  Flexible containers are classified into running containers that are assumed to be used repeatedly for a long period of time and cross containers that are premised on one filling use or that have been used for one year. The As the former running container, a container in which polyester fiber is mainly used as a base fabric and flexible soft vinyl chloride, EVA, polyurethane, rubber or the like is laminated on both front and back surfaces is used. On the other hand, in the latter cross container, there are a cloth made mainly of polyolefin resin fibers and no inner bag depending on the content to be filled, and a container having an inner bag inside the cross container.

  For example, when filling a powder container with a flexible container, in particular in the case of a cross container, in order to prevent the leakage of the powder from the cloth fabric and the seam of the cloth, or to prevent external contamination, water vapor In order to avoid contact with gas, etc., a double structure is adopted in which an inner bag made of a single layer or multilayer plastic film using a polyolefin film or a gas barrier material is enclosed in an outer bag made of cloth cloth. Things have been done.

  However, since the granular material is filled in the state of embracing the air due to its particle size / shape, etc., the actual bulk density of the flexible container contents is reduced. Since almost no load is applied, the tendency to become smaller than the set specific gravity becomes remarkable. Thereafter, with the lapse of time immediately after filling, the filling height gradually decreases, and after several hours, the filling height may decrease by a few tens of centimeters, and the content filling capacity may decrease (filling). Efficiency issues). In addition, if the flexible container is stacked in two or three layers on a flat stacked flexible container with the air remaining in the flexible container by closing the inlet of the inner bag after filling, The third stage is inclined and becomes very unstable. As a result, the stacked flexible containers cannot be brought into close contact with each other, resulting in a loss of storage space and a safety problem due to the risk of falling of the stacked flexible containers. There is a problem such as unavoidable (problem with filling shape).

  Conventionally, a proposal as described in Patent Document 1 has been made for the above problem. In this proposal, a check valve is provided in a plurality of through holes provided in a flexible container inner bag to achieve deaeration. However, in this proposal, by providing a check valve in each through hole, not only the ventilation of the valve is remarkably inhibited, but considering the mechanical strength, the number of through holes with check valves is not limited. There is a problem that there are limitations.

JP 2001-199498 A

  In view of the above circumstances, the present invention reduces the amount of filling of the flexible container, and in terms of storage space loss and safety problems resulting from the instability of the upper flexible container when stacking this, An object of the present invention is to provide a flexible container that can solve problems related to filling efficiency and filling shape and can be stably stacked.

  According to the present invention, the object is to provide an inner bag made of at least one layer of a plastic film having a deaeration mechanism, and a breathable outer bag having a trunk portion, an upper surface, and a lower surface, and interior the inner bag. It is achieved by a flexible container characterized by comprising.

  The degassing mechanism is capable of degassing the air remaining in the inner bag after the filling of the flexible container of the present invention through the inner bag without the leakage of the filler and the entry of foreign matter from the outside. Any mechanism and structure can be used without particular limitation. As the deaeration mechanism, for example, it is preferable to use a plurality of deaeration hole groups penetratingly installed inside and outside the inner bag. . This is because the plastic film in the inner bag can be perforated and formed on the production line by a simple method, and it is not necessary to incorporate other materials and the cost can be reduced.

  When a plurality of deaeration holes are used as the deaeration mechanism, they can be provided in at least a part of the inner bag. Here, the term “at least a part” is not limited to a partial region of the inner bag, and is used to include the entire surface. When the plurality of deaeration holes are provided in the region, they can be arranged and formed in a pattern having a certain regularity continuously or intermittently in the circumferential direction of the inner bag or in a direction perpendicular thereto. This pattern can be provided in the circumferential direction in the upper end edge region of the trunk portion of the outer bag or the outer peripheral region of the upper surface.

  In the present invention, as described above, the flexible container has a double structure including the inner bag having a deaeration mechanism and the outer bag having air permeability, so that the rigidity necessary for lifting and transporting the packing is obtained. The air remaining inside the inner bag can be effectively degassed while securing.

It is a perspective view which shows the external shape of one Embodiment of the flexible container of this invention. It is a schematic diagram which shows an example of the pattern of several deaeration holes. It is an enlarged view in a square frame in FIG. 2A. It is a schematic diagram which shows another example of the pattern of several deaeration holes. It is a schematic diagram which shows another example of the pattern of several deaeration holes. It is a schematic diagram which shows another example of the pattern of several deaeration holes. It is a schematic diagram which shows another example of the pattern of several deaeration holes. It is a schematic diagram which shows another example of the pattern of several deaeration holes. It is a schematic diagram which shows another example of the pattern of several deaeration holes. It is a perspective view which shows the external shape of another embodiment of the flexible container of this invention.

  Next, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing an example of an embodiment of a flexible container of the present invention. 2A schematically shows the arrangement of the deaeration holes in the inner bag of the flexible container shown in FIG. 1, and FIG. 2B shows an enlarged view inside the square frame in FIG. In addition, in FIG. 2, the state which folded the inner bag along the direction orthogonal to the circumferential direction (direction from an injection | throwing-in part to a discharge | emission part. This direction corresponds to the up-down direction of a flexible container normally) is typical. It is shown as a rectangle.

  As shown in FIG. 1, the flexible container 1 of this embodiment is comprised from the inner bag 20 which consists of a 1 layer plastic film provided with a deaeration mechanism, and the outer bag 10 which equips this inside.

(1) Inner bag 20
The inner bag 20 is composed of at least one layer of plastic film. Specific examples of the material for the plastic film include polyolefin resin, ethylene-vinyl acetate copolymer, nylon, polyvinyl alcohol, and polystyrene. These can be used alone or in appropriate combination. In addition, in this invention, if a deaeration mechanism can be provided in the range of the thickness of the plastic film mentioned later, it will not be limited to these materials.

  Specific examples of the polyolefin resin include polyethylene and polypropylene. When polyethylene is used, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), high density polyethylene (HDPE), metallocene polyethylene and the like having a density in the range of 0.900 to 0.960 can be used. These polyolefin resins can be used as raw materials alone or in combination.

  The raw material for the plastic film may further contain a resin (modifier) such as an olefinic thermoplastic elastomer (TPO). TPO is an elastomer (rubber, such as polypropylene, hard segment, and polyethylene, an elastomer having a small amount of ethylene and a diene component, ethylene-propylene-diene rubber (EPDM), ethylene-propylene rubber (EPR), styrene elastomer). ) Is a soft segment, and these are obtained by simply kneading and blending them mechanically. Further, those obtained by adding an organic peroxide to the soft segment and partially crosslinked, and those obtained by graft-modifying the soft segment with an unsaturated hydroxy monomer or an unsaturated carboxylic acid derivative are also included. These various thermoplastic elastomers can be used alone or in combination of two or more.

  The content ratio of TPO is preferably set to 0 to 40% by weight when the entire inner bag 20 is 100% by weight. This is because if the TPO content exceeds 40% by weight, the physical strength deteriorates.

  In addition to the resins, the plastic film material may contain other resins and various additives as necessary. For example, for the purpose of modifying the film, additives such as a weathering agent, an antistatic agent, and an antioxidant can be added as necessary without affecting the properties of the plastic film.

  The raw material thus prepared is put into a heated cylinder from a hopper of an inflation molding machine, sent with a screw while being kneaded in a completely molten state, passed through an annular die, and blown air from its lip portion. It is extruded into a cylindrical shape, cooled with an air ring, pulled up with a pinch roll, and continuously formed into a polyethylene raw material (cylindrical film) in a crushed state. The blow ratio by air blowing at this time is an important factor for determining the orientation balance of the film, and is preferably set to 1.0 to 3.0.

  Further, as a method for forming the film into a cylindrical shape, for example, the film is first formed into a film by a conventionally known T-die forming method, calendar forming method or stretching method, and then the both ends in the length direction or width direction of the film are formed. You may shape | mold into a cylindrical film by heat-sealing together.

  The thickness of the one-layer plastic film thus obtained can be set in the range of 30 to 200 μm, preferably 30 to 170 μm, more preferably 30 to 150 μm. As will be described later, when MP holes are employed as a plurality of deaeration holes, if the thickness exceeds the above range, it becomes difficult to perforate by the microperforation device. This is because damage may occur.

(Deaeration mechanism)
The cylindrical plastic film constituting the inner bag 20 is provided with a plurality of deaeration hole groups 29, 29,... Penetrating into and out of the inner bag 20 as a deaeration mechanism. The reason why the deaeration hole group is provided in this way is that the plastic film of the inner bag can be perforated by a simple method on the production line, and it is not necessary to incorporate other materials and the cost can be reduced. The plurality of deaeration hole groups 29, 29,... Are arranged in a direction perpendicular to the circumferential direction of the plastic film (usually coincides with the vertical direction of the flexible container 1 of the present invention) and the band-shaped array 25 having a predetermined width. Has been. Each deaeration hole 29 can deaerate the air remaining in the inner bag 20 naturally or with an increase in internal pressure in the inner bag 20 after the filling (not shown) of the flexible container 1 of the present invention is filled. And the inner bag 20 is formed so that there is no leakage of the filling material or contamination from outside.

  The average hole diameter of each deaeration hole 29 can be set to 0.01 mm or more. Since the maximum value of the hole diameter of the deaeration holes 29 cannot be generally described because it differs depending on the type of the filling material filled in the flexible container 1 of the present invention, a case where the filling material is, for example, a lump is assumed. In this case, the maximum average pore diameter can be set to 10 mm.

  Usually, when the flexible container 1 of the present invention is used for filling the granular material, the plastic film of the inner bag 20 has a plurality of fine particles formed by a perforation technique using a micro perforation device or a laser device. It is preferable to drill holes (hereinafter simply referred to as “MP holes”) and use these as deaeration holes. Here, the micro perforation apparatus, for example, allows the plastic film to pass between both rolls while pressing a needle roll having numerous fine needles implanted on the outer periphery against the rubber roll with a predetermined pressing pressure. It is an apparatus capable of forming fine holes. In this case, the average pore size required for each MP hole 29 depends on the type and particle size of the powder particles to be filled, but cannot be generally stated, but is usually 0.01 to 0.5 mm, preferably 0.01 to 0. .3 mm, more preferably 0.01-0.2 mm.

  In addition, when the deaeration hole group is an MP hole group, the air permeability according to the Gurley method of the MP hole groups 29, 29,... In the array 25 is set to 300 seconds or less, preferably 30 to 300 seconds. It is good. The number of the MP hole groups per unit area is made constant so that the air permeability of the MP hole groups 29, 29,... Is included in the above range, and the average pore diameter is increased, or conversely the average of the MP holes The number of holes can be increased by keeping the hole diameter constant.

  Further, when the deaeration hole group is an MP hole group, the air permeation rate per 20 pieces collected in an arbitrary continuous small region in the region of the inner bag 20 using the air permeation rate as another index for deaeration. The speed (aeration speed) may be set to 0.33 ml / second or more, preferably 0.33 to 2 ml / second. When the air permeation speed of the MP hole groups 29, 29,... Needs to be adjusted to the above range, the average hole diameter of each MP hole 29 may be changed.

  The arrangement 25 of the MP holes 29, 29,... Shown in FIG. 1, FIG. 2A and FIG. It is obtained by continuously drilling using a micro perforation device. In this case, since the plastic film is flowed in a folded state, the perforation by the microperforation device is performed at the upper and lower opposing portions of the plastic film (see FIG. 1).

  The width of the array 25 is determined by the width of the fine needles implanted in the needle roll of a micro perforation device (not shown). The needle implantation width is usually set in the range of 20 to 150 mm, preferably 50 to 150 mm, more preferably 80 to 100 mm, but is not limited to this range, and the MP holes 29, 29,. .. When the target value of the air flow rate (ventilation speed) through the surface is defined, the hole diameters and drilling pitches of the MP hole groups 29, 29,. Alternatively, the width may be kept constant and the hole diameters and drilling pitches of the MP hole groups 29, 29,...

  The pitch of adjacent MP holes in the array 25 can be set to, for example, 5 mm to 15 mm in consideration of the balance between the strength and breathability of the inner bag 10 and the target of the air flow rate.

  In addition, each of the MP holes in the array 25 is capable of accurately grasping the average pore diameter as described above, the air permeability, and whether the plastic film passing through the micro perforation apparatus is folded in two and is one or two sheets. From the viewpoint of improving accuracy in predicting the target value of the air permeation speed, it is preferable that the shape be as uniform as possible. This is also true when a flexible container having an inner bag having the array 25 is actually used. In order to improve the shape of the MP hole, the pressure on the needle roll is adjusted according to the material and thickness of the plastic film, and the roll on the side to which the needle roll is pressed by changing the surface material (receiving roll) ) Surface hardness can be changed. For example, in the case of a polyethylene inner bag having a thickness of 0.07 μm, if the receiving roll is made of urethane having a surface hardness of 70, the pressing force of the needle roll is normally set to 3 kgf, and the inner bag made of polyethylene having a thickness of 0.05 mm is used. In this case, it is set to 2 kgf. Further, as another method for improving the MP hole shape, the apparent surface hardness may be reduced by winding a polyolefin cross sheet such as polyethylene or polypropylene around the receiving roll without replacing the surface material of the receiving roll. The adjustment of the pressing pressure and the replacement of the surface material or the winding of a cross sheet around the receiving roll can be appropriately combined.

  When the MP hole array 25 is provided in a partial region of the inner bag 20, the array 25 is not limited to the embodiment shown in FIGS. 1, 2A and 2B, and the circumferential direction of the inner bag 20 or orthogonal thereto. It can be arranged and formed in a pattern having a certain regularity in the direction continuously or intermittently. FIGS. 3A to 3C and FIGS. 4A to 4C show examples of other embodiments of the MP hole array 25. FIG.

  3A shows a predetermined width array 25, FIG. 3B shows a predetermined width zigzag array 25, and FIG. 3C shows a predetermined width dashed line array 25 in a direction perpendicular to the flow direction of the plastic film. It is arranged. Among these, the arrangement pattern shown in FIG. 3A or 3C is preferably arranged so as to be provided in the circumferential direction in the upper end edge region of the body portion of the outer bag 10 or the outer peripheral region of the upper surface. FIG. 5 shows an embodiment in which the array 25 is formed as shown in FIG. 3A in the embodiment shown in FIG. 1, and other configurations are essentially the same.

  4A shows an arrangement 25 in which the width continuously increases or decreases in the flow direction of the plastic film, and FIG. 4B shows a zigzag arrangement 25 having a predetermined width that is continuously perforated in the flow direction of the plastic film. . By providing the inner bag 20 with the pattern of FIG. 4A, the air permeability per unit area is relatively larger when the outer bag 10 is disposed near the upper surface 12 or the surface than the lower surface 16. You may make it show quantity (air permeability speed). FIG. 4C shows an array 25 having a predetermined width provided intermittently in the flow direction of the plastic film.

  As described above, in the present invention, the plastic film is caused to flow through the microperforation apparatus in a direction perpendicular to the flow direction, the roll width in the needle roll and the needle implantation are changed, or the plastic film is intermittently sandwiched and punched. In addition to the embodiments illustrated in FIGS. 3A to 3C and FIGS. 4A to 4C, a wide variety of patterns having a certain regularity can be obtained. Also, by changing the position of the microperforation device and laser device in the direction perpendicular to the flow direction of the plastic film flowing in the manufacturing process, and flowing the plastic film again, it is constant at different positions in the circumferential direction. A plurality of MP hole patterns can be provided repeatedly at intervals of. Furthermore, when perforating with a microperforation device or the like in the circumferential direction of the plastic film, the position of the device is similarly changed, and the MP holes are repeatedly formed at a constant interval in the direction perpendicular to the circumferential direction of the plastic film. A pattern can be provided.

  The plurality of MP holes (deaeration holes) 29, 29,... Are not limited to the embodiment shown in FIGS. 1 to 4C provided in a partial region of the inner bag 10, and are provided on the entire surface of the inner bag 10. You can also. The pattern of the MP holes arranged on the upper surface 12 of the outer bag 10 or closer to the surface may exhibit a relatively higher air permeability per unit area than that arranged on the lower surface 16 side. Good.

  In addition, in the present invention, the MP holes (deaeration holes) 29, 29,... Are used in combination with a through hole provided inside and outside separately and a valve (including a check valve) attached. This is not excluded.

(2) Outer bag 10
The outer bag 10 has a rectangular tubular body 11 and suspension belts attached to the flexible container 1 of the present invention above the four corners of the body 11 via stitching parts 31, 31, 31, 31 respectively. 30, 30, 30, 30 (in this specification, the direction in which each suspension belt 30 extends from the trunk portion 11 is “upper”, and the opposite side of the trunk portion 11 in the opening direction is “lower”. ), An upper surface 12 that closes the upper opening of the body 11, and a lower surface 16 that closes the lower opening of the body 11. In the outer bag 10 according to the present embodiment, the rectangular tubular body 11, the upper surface 12, and the lower surface 16 have air permeability. A central region of the upper surface 11 is opened, and one opening end of the cylindrical insertion portion 13 is fixed to the opening, and an edge of the opening is formed on the upper lids 14, 14,. The proximal end is attached. Further, the central region of the lower surface 16 is similarly opened, and one opening end of the cylindrical discharge portion 17 is fixed to the opening, and the lower lids 18 and 18 of the chrysanthemum crack structure are formed on the edge of the opening. The proximal end side of... Is attached. The upper lids 14, 14,... And the lower lids 18, 18,. By squeezing these tapes 15 and 19, the upper cover 13 and the lower cover 18 respectively close the openings of the upper surface 12 and the lower surface 16 in a state in which the input portion 13 and the discharge portion 17 are taken in, respectively. . In addition, about the external shape of the outer bag 10, it does not restrict | limit especially in this embodiment, The structure which does not have the discharge part 17 in the center area | region of the lower surface 16 of the square cylindrical trunk | drum 11 may be sufficient.

  Moreover, it does not restrict | limit especially about the raw material of the outer bag 10, Various materials currently used for the conventionally well-known cross container etc. can be used. For example, a yarn fabric obtained by weaving a flat yarn made of a polyolefin resin such as polyethylene or polypropylene as a warp and a weft with a loom can be suitably used.

Next, the present invention will be described in more detail with reference to preferred embodiments of the flexible container of the present invention.
[Production of inner bag]
As shown in FIG. 1, FIG. 2A and FIG. 2B, a perforation process of MP holes into a strip having a width of 100 mm is performed continuously on the inner bag made of polyethylene having a thickness of 0.070 mm in the flow direction of the inner bag by a micro perforation apparatus. went. The inner bag is manufactured in a cylindrical shape by an inflation film forming apparatus, and this cylindrical film is folded in half and passed through the microperforation apparatus. Therefore, the inner bag is paired with each of the upper and lower films, that is, on the circumference of the inner bag. An array of strip-shaped MP holes with a width of 100 mm was formed at the corners. In this arrangement, the diameter of each MP hole was 0.100 mm, and the pitch between adjacent MP holes was 6 mm.

[Production of outer bag]
A flat yarn made of polypropylene was produced, and the yarn was woven with a loom using warp and weft to obtain a yarn fabric. Using this yarn fabric, a cylindrical body portion and an upper input portion were formed, and these were sewn by sewing to produce a cylindrical outer bag. This outer bag corresponds to a normal cross container. A flexible container having an inner / outer double structure was produced by lining the inner bag in the outer bag thus obtained.

  The flexible container thus obtained was filled with powder particles. During filling up to the middle stage of the flexible container, the air entrapped by the dead weight of the granular material was naturally discharged from the filling port and the MP hole. When the filling height is further increased, the compressing action due to the weight of the granular material is reduced, so that the granular material filling is in a state of embracing air. In order to prevent foreign matter from entering, after tying the top inlet and closing it with an upper lid, the flexible container is stacked and pressure is applied from above to finally deaerate the entire top surface of the flexible container. It can be flattened, and stable stacking can be achieved in about 2 to 3 minutes and at the latest about 5 minutes.

  As described above, the flexible container of the present invention is a double container comprising an inner bag made of at least one layer of plastic film provided with a deaeration hole as a deaeration mechanism, and an outer bag that is breathable and has an inner bag. Since it has a structure, it can be degassed naturally or effectively, and the entry of foreign matter can be prevented. In particular, it can be processed continuously or batchwise in the existing inner bag manufacturing process, is suitable for mass production, has little variation in the finished shape, and can assure stable quality. Further, even if a deaeration hole is provided, the physical property value required for the plastic film is not greatly affected, and therefore it can be handled in the same manner as a normal inner bag.

  The present invention is not limited to the above-described embodiment, and can be embodied by modifying the constituent elements without departing from the gist thereof. The present invention can also be applied to a pallet-integrated flexible container and a flexible container having a pocket capable of accommodating a forklift claw at the bottom. In addition, the present invention is not limited to application to a flexible container that is provided with a suspension belt and is suspended from above.

1, 2 Flexible container 10 Outer bag 11 Body 12 Upper surface 13 Upper surface inner lid 14 Upper lid 15 Binding tape 16 Lower surface 17 Lower surface inner lid 18 Lower lid 19 Binding tape 20 Inner bag 21 Cylindrical body 22 Inner bag upper surface 23 Input unit 24 Input port 25 (deaeration hole group) arrangement 26 inner bag lower surface 27 discharge part 28 discharge port 29 deaeration hole 30 suspension belt 31 stitching part

Claims (10)

  A flexible, comprising an inner bag made of at least one layer of plastic film having a deaeration mechanism, and a breathable outer bag having a trunk portion, an upper surface and a lower surface and having the inner bag inside. container.   The flexible container according to claim 1, wherein the deaeration mechanism is a group of deaeration holes provided at least in a region of the inner bag.   The flexible container according to claim 2, wherein an average pore diameter of the deaeration hole group is in a range of 0.01 to 10 mm.   The flexible container according to claim 2 or 3, wherein the air permeability of the degassing hole group by Gurley method is 300 seconds or less.   4. The flexible container according to claim 2, wherein the air permeation speed of the deaeration hole group is 0.33 ml / second or more per 20 pieces gathered in an arbitrary continuous small region in the region.   The said deaeration hole group is arrange | positioned and formed by the pattern with fixed regularity continuously or intermittently in the circumferential direction of the said inner bag, or the direction orthogonal to this, The any one of Claims 2-5 The flexible container of item 1.   The flexible container according to claim 6, wherein the pattern of the deaeration hole group is provided in a circumferential direction in an upper end edge region of the body portion of the outer bag or an outer peripheral region of the upper surface.   When the pattern of the deaeration hole group is disposed on the entire surface of the inner bag, or is disposed in a direction orthogonal to the circumferential direction of the inner bag, the pattern of the deaeration holes should be disposed on the upper surface or closer to the surface. The flexible container according to claim 6, which shows a relatively large air permeation amount per unit area per unit area rather than being arranged closer to the lower surface.   The flexible container according to claim 1, wherein the plastic film is made of a polyolefin resin. The flexible container according to claim 1, wherein the plastic film has a thickness in a range of 30 to 200 μm.

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