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(11) | EP 1 431 207 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Gusset bag |
| (57) A gusset bag comprises a pair of opposing flat surface portions (3), a pair of side
surface portions (4) connected, at side edge portions thereof, to side edge portions
of the flat surface portions, respectively, the side surface portions having gusset
portions formed by inwardly folding the side surface portions, a bottom portion closing
one end of the tubular body so as to provide a gusset bag body (2A), and a folding
auxiliary portion formed to the bottom portion of the gusset bag body to a portion
outside an outer end edge of the content accomodation portion (10) of the gusset bag
body for assisting folding of the bottom portion along a folding line to thereby easily
provide a flat bottom surface. |
BACKGROUND OF THE INVENTION
Field of The Invention
[0001] The present invention relates to a gusset bag of a self-standing structure capable of stably standing at a time when the gusset bag is filled up with an inner content.
Relevant Art
[0002] In conventional art, there is known, as a self-standing packaging or package bag, a standing pouch or flat-bottom type gusset bag, and some techniques have been applied to such packaging bags to ensure a high standing ability. In one example, a bottom portion of the bag is formed with a flat member or like.
[0003] On the other hand, there is also provided a gusset bag which is not provided with a flat bottom member, in which a bottom portion of the bag is folded so as to provide a flat bottom portion (having flat bottom surface area) and, hence, ensure the self-standing property. For example, as such gusset bag, there is disclosed a gusset bag in Japanese Patent Laid-open (KOKAI) Publication No. 2001-199452, in which, at an outside portion of an inner content accommodation portion of a gusset bag which is filled up with the content, a flat surface portion and side surface portion are heat sealed , i.e., thermally sealed with heat, so as to provide a triangular shape, and score lines extending laterally are formed to these heat-sealed portions as portions to be bent therealong so as to easily bent the bottom portion of the gusset bag.
[0004] In such known art or technology as mentioned above, however, in the structure that the score lines are formed as described, there may cause a fear that these lines are expanded in the lateral direction, which may adversely result in breakage of the gusset bag itself, thus being inconvenient and defective.
SUMMARY OF THE INVNETION
[0005] The present invention was conceived by taking the above matters into consideration and an object of the present invention is therefore to substantially eliminate defects or drawbacks encountered in the prior art mentioned above and to provide a gusset bag having an improved stable self-standing property or structure by folding a bottom portion of the gusset bag without giving any damage thereto.
[0006] This and other objects can be achieved according to the present invention by providing, in one aspect, a gusset bag comprising:
a pair of opposing flat surface portions;
a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, so as to provide a tubular body having openings at top and bottom end portions thereof, the side surface portions having gusset portions formed by inwardly folding the side surface portions so that the inwardly folded gusset lines are opposed to each other when the side surface portions are applied to the flat surface portions;
a bottom portion closing one end open portion of the tubular body so as to provide a gusset bag body, said the other one end open portion being formed as a take-out portion through which an inner content filling a content accommodation portion of the gusset bag body is taken out; and
a folding auxiliary portion formed to the bottom portion of the gusset bag body at a portion outside an outer end edge of the content accommodation portion of the gusset bag body and adapted to assist folding of the bottom portion along a folding line to thereby easily provide a flat bottom surface,
wherein the folding auxiliary portion is formed as a through hole at a portion at least one of the flat surface portion and the side surface portion, the through hole being a hole elongated in a direction so as to accord with a direction along which a folding line of the bottom portion extends.[0007] In modified aspects, the folding auxiliary portion may be formed as a recessed portion by reducing a thickness of the bottom portion of the gusset bag body. The recessed portion is formed in a manner that a through hole is formed to the side surface portion and the through hole is then covered up by bonding the flat surface portion to the side surface portion.
[0008] The folding auxiliary portion may be formed as a coarse surface portion composed of aggregation of a number of fine holes formed to at least one of the flat surface portion and the side surface portion.
[0009] The folding auxiliary portion may be formed to at least one of the flat surface portion and the side surface portion and composed of a linear cut-out formed so as to extend in a width direction of the gusset bag body and a crack-spreading prevention portions formed to both end portions of the linear cut-out. Each of the crack-spreading prevention portions is a circular-arc continuous to the end portion of the linear cut-out.
[0010] In the above aspects, the folding auxiliary portion may be formed to at least one of the flat surface portion and the side surface portion positioned on one side in the thickness direction of the gusset bag body with the folding line formed to the side surface portion being boundary thereof.
[0011] The folding auxiliary portion may be formed to one of the flat surface portion and to a portion of the side surface portion on the other side flat surface portion side from the folding line formed to the central portion of the side surface portion.
[0012] The bottom portion may have a portion positioned inside the folding line when the bottom portion is folded and the folded line having a recessed shape is overlapped with the folding auxiliary portion at the folding auxiliary portion forming portion.
[0013] According to the above aspects of the gusset bag of the present invention, the following advantageous functions and/or effects will be achieved.
[0014] That is, by providing the folding auxiliary portion to the bottom portion of the gusset bag body, the rigidity of this portion is reduced, thus easily folding the bottom portion and then forming it to be flat, whereby the gusset bag having an improved self-standing structure can be provided.
[0015] Furthermore, according to the embodiment in which the folding auxiliary portion is composed of the linear cut-out and the crack-spreading prevention portions, preferably in shape of circular-arc, formed to both ends of the linear cut-out extending in the width direction of the bag body, the generation and the spreading of the crack can be effectively prevented. In addition, the spreading of the crack can be further prevented by forming the circular-arc portion so that the tangential line at this portion directs downward of the gusset bag body. In this example, the spreading of the crack towards the inner content accommodation portion of the bag body can be also prevented.
[0016] Moreover, in the example, in which the folding auxiliary portion is formed to at least one of the flat surface portion and the side surface portion positioned on one side in the thickness direction of the gusset bag body with the folding line formed to the side surface portion being boundary thereof, the direction along which the bottom portion is folded can be easily determined, thus being advantageous.
[0017] According to the embodiment, in which the folding auxiliary portion is formed from the recessed portion, a good outer appearance of the gusset bag can be provided.
[0018] Still furthermore, in the example, in which the bottom portion has a portion positioned inside of the folding line when the bottom portion is folded and the folded line having a recessed shape is over lapped with the folding auxiliary portion at the folding auxiliary portion forming portion, since the folding line is independently formed, the folding direction along which the bottom portion of the gusset bag body is folded can be easily determined with the recessed surface being the inside thereof.
[0019] The take-out portion may be composed of a take-out device which comprises a take-out tube and a cap engaged with the take-out tube, one end of the take-out tube being inserted into the bag body and the other one end projecting outward therefrom, and the take-out tube is clamped between the one (top) edge portions of the flat surface portions and then tightly sealed thereto at a peripheral portion thereof.
[0020] In a further aspect of the present invention, there is provided a gusset bag which comprises a pair of opposing flat surface portions and a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, through a fusing treatment so as to provide a tubular body having openings at longitudinally top and bottom end portions thereof, the side surface portions having gusset portions formed by inwardly folding the side surface portions, and in which inner surfaces of the flat surface portions and the side surface portions are fused so that the fused side portions of the flat and side surface portions of the tubular body and the fused bottom portion thereof are connected to thereby form triangular heat-seal portions,
wherein a folding auxiliary portion for assisting folding of the bottom portion of the tubular body to thereby easily form a flat portion to the bottom portion to the heat-seal portion at which one of the triangular heat-seal portions is formed by fusing at least one of the flat and side surface portions, and the folding auxiliary portion comprises at least one score line, which is composed of a linear portion formed so as to accord with a position to which a folding line along which the bottom portion of the gusset bag body is folded and circular-arc portions formed at both ends of the linear portion.
[0021] In a still further aspect, there is provided a gusset bag which comprises a pair of opposing flat surface portions and a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, through a heat-seal treatment so as to provide a tubular body having openings at longitudinally top and bottom end portions thereof, the side surface portions having gusset portions formed by inwardly folding the side surface portions , and in which inner surfaces of the flat surface portions and the side surface portions are heat-sealed so that the heat-sealed side portions of the flat and side surface portions of the tubular body and the heat-sealed bottom portion thereof are connected to thereby form triangular heat-seal portions,
wherein a folding auxiliary portion for assisting folding of the bottom portion of the tubular body to thereby easily form a flat portion to the bottom portion to the heat-seal portion at which one of the triangular heat-seal portions formed by heat-sealing at least one of the flat and side surface portions, and the folding auxiliary portion comprises a through hole formed to the side surface portion of the tubular body and the through hole is a hole elongated in a direction to accord with a direction along which a folding line of the bottom portion extends so that the folding auxiliary portion is covered up by the flat surface portion.
[0022] According to these embodiments, the bottom portion of the gusset bag body can be also easily folded in the predetermined direction and the folded state, i.e., flat bottom shape, can be surely maintained. Thus, the self-standing ability of the gusset bag body can be also obtained.
[0023] In addition, the spreading of the cracks from the folding auxiliary portion can be effectively prevented.
[0025] The nature and further characteristic features of the gusset bag of the present invention will become further clear from the following descriptions made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In the accompanying drawings:
Fig. 1 is a plan view showing a gusset bag according to a first embodiment of the present invention;
Fig. 2 is a sectional view, in an enlarged scale, taken along the line II-II in Fig. 1;
Fig. 3 is a sectional view, also of Fig. 2, showing an example of a folding auxiliary portion acting as bonded (joined) portion;
Fig. 4 is a sectional view, in an enlarged scale, taken along the line IV-IV in Fig. 1;
Fig. 5 is a perspective view showing a gusset bag according to the embodiment of the present invention as viewed from a bottom side portion thereof shown in Fig. 1;
Fig. 6 includes Figs. 6A to 6F showing examples of the folding auxiliary portion such as shown in Fig. 2 or 3;
Fig. 7 is a plan view showing a gusset bag according to a second embodiment of the present invention;
Fig. 8 is a sectional view, in an enlarged scale, taken along the line VIII-VIII in Fig. 7;
Fig. 9 is an illustration of one example of a folding auxiliary portion formed to the gusset bag of Fig. 7;
Fig. 10 is a sectional view, in an enlarged scale, taken along the line X-X in Fig. 7;
Fig. 11 is an illustration of another example of a folding auxiliary portion formed to the gusset bag of Fig. 7;
Fig. 12 is an illustration showing a folding auxiliary portion formed with a score line;
Fig. 13 is an illustration showing an example of a folding auxiliary portion formed with a crack-spreading (transmitting) prevention portion which is circularly cut out;
Fig. 14 is an illustration also showing an example of a folding auxiliary portion formed with a crack-spreading (transmitting) prevention portion which is folded upward;
Fig. 15 includes Figs. 15A to 15F showing other examples of the folding auxiliary portion;
Fig. 16 is a plan view showing a gusset bag according to a third embodiment of the present invention;
Fig. 17 is a sectional view, in an enlarged scale, taken along the line XVII-XVIII in Fig. 16;
Fig. 18 is a sectional view, in an enlarged scale, taken along the line XVIII-XVIII in Fig. 16;
Fig. 19 is an illustration, in an enlarged scale, of a portion to which one example of a folding auxiliary portion is formed;
Fig. 20 is an illustration, in an enlarged scale, of a portion to which another example of a folding auxiliary portion is formed; and
Fig. 21 includes Figs. 21A to 21F showing other examples of portions to which further examples of the folding auxiliary portion are formed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] Preferred embodiments of the present invention will be described hereunder with reference to the accompanying drawings.
[0028] Further, it is first to be noted that terms such as "upper", "lower", "lateral", "up", "down" or like are used herein with reference to a gusset bag having an upper portion to which a content take-out portion is formed and a lower portion to which a bottom of the gusset bag is formed.
[First Embodiment 1]
[0029] With reference to Fig. 1 showing a plan view of the first embodiment of a gusset bag of the present invention, a gusset bag 1A comprises a bag body 2A composed of a pair of opposing flat portions (flat surface portions) 3, 3 and a pair of side portions (side surface portions 4, 4) connecting both side edges of the flat portions 3, 3, respectively. The thus formed bag body 2A has an upper (top) end edge to which a take-out device 20 for taking the inner content out of the gusset bag body 2A is mounted or provided.
[0030] The flat surface portions 3, 3 of the bag body 2A are formed from film members each in shape of rectangular, and these rectangular film members are opposed to each other so as to constitute the front and back surfaces of the bag body 2A.
[0031] On the other hand, each of the side surface portions 4, 4 is formed from a film member in shape of rectangular, and the rectangular side surface film member 4 is folded along its longitudinal central line 5 so as to form a gusset in the manner that when both the side surface portions 4, 4 are joined to both the flat surface portions 3, 3, the inwardly folded center lines 5, 5 of both the side surface portions 4, 4 are opposed to each other.
[0032] The side edges of the respective flat surface portions 3, 3, and the side edges of the respective side surface portions 4, 4 are thermally fused and joined to each other so as to form heat-seal portions 6, 6 on both the side portions of the bag body 2A. In addition, an upper heat seal portion 7 and a lower heat-seal portion 8 are respectively formed to the upper and lower edge portions of the bog body 2A by thermally fusing the flat surface portions 3, 3 and the side surface portions 4, 4 to each other. Through such thermally fusing, i.e., heat sealing, processes, the peripheral portions of the flat and side surface portions 3 and 4 are fused and sealed to provide a tubular bag body 2A which define an inner accommodation portion 10 which can be filled up with the inner content.
[0033] Further, as the film members forming the flat and side surface portions 3 and 4, laminate films composed of a plurality of film materials which are laminated are utilized. For example, the following laminate films may be utilized.
PET(12µ)/DL/Al(9µ)/DL/ON (15µ)/DL/CPP (50µ) and
PET(12µ)/DL/ON(15µ)/DL/AL(15µ)/DL/CPP(50µ)
(Layers from the outer side of the bag body 2A in the described order).
[0034] The outer layer (PET) is formed from a film material formed of synthetic resin such as polyester type (series), polyamide type, polypropylene type, polycarbonate type, polyacetal type, or like type synthetic resin. Furthermore, non-oriented, uniaxially oriented or biaxially oriented film may be utilized as such film material, and the thickness of the film is not specifically limited to 12µm and will be determined in consideration of the minimally required strength, manufacturing cost and like, usually in a range of 12µm to 25µm.
[0035] Moreover, in some cases, the synthetic resin as the outer layer may be printed on its inner surface, so that it may be required for such outer layer to have a property or performance suitable for printing, and in this meaning, the use of the uniaxially or biaxially oriented film may be preferably utilized. Synthetic paper, cellophane, paper, unwoven fabric or like may be utilized alternately as occasion demands.
[0036] On the other hand, as the inner layer, there are utilized one or more kinds of resins such as for example, low density polyethylene, intermediate (middle) density polyethylene, high density polyethylene, straight-chain (linear) low density polyethylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-acrylic acid methyl copolymer, ethylene-metacrylic acid copolymer, polypropylene, ethylene-propylene copolymer, which are utilized in form of film sheet having thickness of 30 to 200µm.
[0037] A barrier layer is generally formed from aluminium foil and may be formed, for example, from metal foil such as iron, copper or tin, polyethylene terephthalate (PET), polyaimde, polyvinyl chloride, polycarbonate, polyvinyl alcohol, or saponified ethylene-vinyl acetate copolymer, or a film on which polyvinyliden chloride is coated, or a film on which inorganic material such as aluminium, silicon oxide, aluminium oxide, indium oxide, tin oxide, zirconium oxide, magnesium oxide, or a film of polyvinyliden chloride. One or more kinds of the above films may be further utilized in combination. Further, the thickness of the above material for the barrier layer may be set properly in consideration of functions required for gusset bag. Furthermore, it may be generally required for such barrier film to have gas shut-off property, mechanical stiffness, anti-bending property, anti-sticking property, impact-proof property, abrasion-proof property, anti-cold property, heat resisting property, anti-chemical property or like, and the barrier film is hence disposed for suitably attaining such properties or performance for the barrier layer of the gusset bag.
[0038] Further, in order to ensure the barrier performance, there may be disposed, in place of the aluminium foil, a film composed of an outer most deposit layer and a laminate film composed of PET(12µ)/DL/ON(15µ)/DL/AL(15µ)/DL/CPP(50µ). As such deposit (evaporated) layer, there may be utilized aluminium, silicon oxide, indium oxide, tin oxide, zirconium oxide, magnesium oxide or like.
[0039] On the other hand, the take-out device 20 may be mounted to the bag body 2A after the heat-sealing process to the side edges and lower (bottom) end edge 8 of the bag body 2A and before the heat-sealing process to the upper (top) end edge 7 thereof. The take-out device 20 comprises a take-out tube or like member 21 and a cap 22 screw-engaged with the take-out tube 21. The take-out tube 21 has one end inserted into the bag body through an upper end opening of the bag body 2A and the other one end projecting outward therefrom and the cap 22 screw-engaged with the upper end of the take-out tube 21 to close a take-out end opening of the take-out tube 21. The take-out tube 21 is clamped between the upper edge portions of the flat surface portions 3, 3 and then tightly sealed thereto at its peripheral portion by means of heat-seal portion 7 so as not to create any gap between the outer peripheral surface of the take-out tube 21 and the inner surfaces of the flat surface portions 3, 3. After the mounting of the take-out device 20, an inner content is supplied into the bag body 2A, i.e., inner content accommodation portion 10 thereof , and then the mouth portion of the take-out tube 21 is screwed with the cap 22. In this meaning, the take-out device 20 also acts as take-in device through which the inner content is supplied into the bag body 2A.
[0040] The bottom portion of the bag body 2A is provided with the heat-seal portion 8, which has a middle portion 8a having a constant width along the lower edge of the bag body 2A, and on the other hand, whichhas sideendportions 8b, 8bextendingobliquelytowards the heat seal portions 6, 6 so as to form oblique boundaries to the inner content accommodation portion 10 so as to each provide a triangular shape as shown. According to such shape, the lower end of the content accommodation portion 10 provides an upwardly opened shape from the lower edge portion of the bag body 2A.
[0041] In addition, the bottom portion of the bag body 2A is further formed, on the side of the outer edge of the accommodation portion 10 of the bag body 2A, with portions 11 for assisting easy folding ofthebottomportion, which will be called herein folding auxiliary portions 11, 11. In this embodiment, these folding auxiliary portions 11, 11 are through holes formed to the side surface portions 4, 4 folded towards inside between the flat surface portions 3, 3 at both the side portions 8b, 8b of the heat seal portion 8. Each through hole of the folding auxiliary portions 11, 11 has an elliptical (slot) shape having long axis direction along the lower edge of the bag body 2A. That is, as shown in Fig. 1, the folding auxiliary portions 11, 11 have upper and lower edges extending substantially linearly in the width direction of the gusset bag 1A and arcuate side ends connected to the linear edges. As shown in Fig. 2, the folding auxiliary portions 11, 11 thus formed to the folded side surface portions 4, 4 are covered up or hidden from appearance by the outer flat surface portions 3, 3.
[0042] Further, as shown in Fig. 3, the opposed flat surface portions 3, 3 may be bonded to each other by utilizing the folding auxiliary portions 11, 11. According to this example, the folding auxiliary portions 11, 11 can be utilized as bonded portions of the flat surface portions 3, 3, so that it is not necessary to additionally form a bonding portion as in a conventional gusset bag.
[0043] Still furthermore, a folding (folded) line 12 is formed to the portion corresponding to the folded portion of the bottom portion of the bog body 2A so as to extend laterally in the width direction thereof. The folding line 12 is a line to determine the folding direction of the bottom portion of the bag body 2A. As shown in Fig. 4, the folding line 12 is formed by putting and then pressing the bag body 2A in a die so as to provide a recessed shape 12a on the flat surface portion side in the bottom portion folding direction and a protruded shape 12b on the side opposing to the above-mentioned side of the flat surface portion 3. Further, in the example of Fig. 1, the folding line 12 accords with the upper edge of the folding auxiliary portion 11, and the present invention is not limited to such example and may be formed to any portion at which the folding line 12 crosses the folding auxiliary portions 11, 11 in the vertical (longitudinal) direction of the bag body 2A.
[0044] Fig. 5 shows the gusset bag 1A of this embodiment of the state that the bottom portion thereof is folded. With reference to Fig. 5, the rigidity of the bottom portion of the bag body 2A is reduced by the folding auxiliary portions 11, 11 formed to both the lateral sides of the bottom portion, and in addition, the bottom portion can be easily folded to thereby provide a flat structure by the preliminarily formed folding line 12.
[0045] The folding line 12 is formed, as mentioned before, so as to provide the recessed shape 12a on the flat surface portion side in the bottom portion folding direction and the protruded shape 12b on the opposing side of the flat surface portion 3. Further, in the example of Fig. 1, it is possible to fold the bottom portion such that the surface to which the recessed portion 12a is formed is positioned inside the folding line 12. When once folded along such folding line 12, it can be prevented for the bottom portion of the bag body 2A to return to its original shape before the folding because of folding habit formed by the folding line 12, thus maintaining the flatness of the bag 1A and, hence, its standing ability.
[0046] The folding auxiliary portions 11, 11 may be formed in a manner other than the above-mentioned ones with reference to Fig. 2.
[0047] Figs. 6A to 6F are examples showing the folding auxiliary portion formingpositions, in which the folding auxiliary portions are all formed on the outer edge side of the bag body 2A from the content accommodation portion 10 of the bag 1A.
[0048] Fig. 6A shows a state in which slot (i.e., elliptical) shape through holes 11a, 11a are formed to only both the flat surface portions 3a and 3b to thereby form the folding auxiliary portion 11, and the side surface portion 4 is thermally fused to the inner surfaces of the flat surface portions 3a and 3b.
[0049] Fig. 6B shows a state in which the slot-shaped through holes 11a, 11a are formed only to the side surface portion 4 to thereby form the folding auxiliary portion 11. This portion 11 is formed as the through hole 11a formed on one of the flat surface sides 3a with the folding (folded) line 5 being boundary. According to such formation of the folding auxiliary portion 11, the bottom portion of the bag body 2A can be easily bent and folded in a direction in which this flat side surface side 3a is folded inward. That is, by forming the folding auxiliary portion 11, the function for determining the folding direction to the arrowed direction can be attained. Further, the bottomportion will be further easily foldable by positioning the recessed portion 12a of the folding line 12 on the flat surface side 3a at which the folding auxiliary portion 11 is formed.
[0050] Fig. 6C shows a state in which the slot-shaped through hole 11a is formed only to one 3a of the flat surface portions to thereby form the folding auxiliary portion 11. In this case, the bottom portion of the bag body 2A can be easily bent and folded in a direction in which this flat side surface side 3a is folded inward. Further, in this example, the bottom portion will be further easily foldable by positioning the recessed portion 12a of the folding line 12 on the flat surface side 3a at which the through hole 11a is formed, thus also achieving the function for determining the folding direction to the arrowed direction.
[0051] Fig. 6D shows a state in which the slot-shaped through holes 11a, 11a, as folding auxiliary portions 11, 11, are formed to the other one 3b of the flat surface portions and a portion 4b of the side surface portion 4 positioned on the side of the one flat surface portion 3a other than the folding line 5 formed to the central portion of the side surface portion 4 in an asymmetrical shape with respect to the folding line 5. Such asymmetrical arrangement of the through holes 11a, 11a will contribute to easy folding of the bottom portion of the bag body 2A to one flat surface side. That is, the function for determining the folding direction to the arrowed direction can be attained, and in addition, the bottom portion will be further easily foldable by positioning the recessed portion 12a of the folding line 12 on the flat surface side 3a at which the folding auxiliary portion 11 is formed.
[0052] Fig. 6F shows a state in which the slot-shaped through holes 11a, 11a, as folding auxiliary portions 11, 11, are formed to both the flat surface portions 3a and 3b and both portions 4a and 4b of the side surface portion 4 in the thickness direction of the bag body 2A with the folding line 5 being the boundary thereof. According to this example, the through holes are formed through the thickness direction of the bag body 2A, so that the rigidity of these portions is weakened.
[0053] As mentioned above, according to the various example of the present embodiment, the through hole(s), i.e., the folding auxiliary portion(s) 11, can be formed at least one of the flat and side surface portions.
[0054] Further, in the described embodiment, the through hole 11a is defined so as to have a slot (or elliptical) shape expanded in the lateral direction of the bag body 2A, the shape thereof is not limited to such shape and other shape, such as circular or rectangular shape, may be adopted.
[Second Embodiment 2]
[0055] The second embodiment of a gusset bag of the present invention will be represented by Fig. 7, showing a plan view of the gusset bag 1B.
[0056] With reference to Fig. 7, the gusset bag 1B comprises a bag body 2B composed of a pair of opposing flat portions (flat surface portions) 3, 3 and a pair of gusset-shaped side portions (side surface portions 4, 4) connected to both side edges of the flat portions 3, 3, respectively. The thus formed bag body 2B also has the upper (top) end edge to which the take-out device 20 for taking the inner content out of the gusset bag body 2B is mounted or provided, the take-out device 20 composed of the take-out tube 21 and the cap 22 screwed thereto. The detailed explanation of the constructional elements or portions of the gusset bag 1B of this second embodiment corresponding to those of the gusset bag 1A of the first embodiment are omitted herein by adding the same reference numerals.
[0057] The gusset bag 1B is also provided with auxiliary portions 30, 30 for assisting the folding of the bottom portion of the bag body 2B on both lateral sides thereof on the outer edge side of the inner content accommodation portion 10 of the bag body 2B. Each of these folding auxiliary portions 30, 30 is composed of, as shown in Fig. 8, linear cut-outs formed to the flat surface portions 3, 3 in the lateral (width) direction of the bag body 2B and portions preventing crack-spreading provided at both ends of the linear cut-outs.
[0058] That is, as shown in Fig. 9, the folding auxiliary portion 30 is composed of a linear cut-out portion 31 as linearly extending cut-out and circular-arc portions 32, 32 as crack-spreading prevention portions formed to both ends of the linear cut-out 31 so as to provide a downwardly curved shape as viewed.
[0059] The linear portion 31 is formed, as shown in Fig. 7, so as to accord with the forming position of the folding line 12, and by synergistically attaining both the functions of the linear portion 31 and the folding line 12, the bottom portion of the bag body 2B is extremely easily foldable.
[0060] Further, as shown in Fig. 10, the folding line 12 is formed by putting and then pressing the bag body 2B in a die so as to provide a recessed shape 12a on the flat surface portion side in the bottom portion folding direction and a protruded shape 12b on the side opposing to the above-mentioned side of the flat surface portion 3. On the other hand, the circular-arc portions 32, 32 are formed to be continuous to both the ends of the linear portion 31 so as to be curved in the downward direction of the bag body 2B. These circular-arc portions 32, 32 have end edge portions 33, 33 on which tangential lines 45, 45 extend in a direction perpendicular (at right angle) to the extension of the linear portion 31.
[0061] With the gusset bag 1B having the folding auxiliary portions 30, 30 of the structures mentioned above, the bottom portion of the bag body 2B is folded with the linear line 31 of the folding auxiliary portion 30 being the reference or base line. Moreover, at the linear line forming position, the rigidity of the film member constituting the bag body 1B is weakened by the formation of the folding auxiliary portion 30, so that the bottom portion of the bag body 2B becomes extremely easily foldable by the synergistic effect and function of the folding auxiliary portion 30 and the folding line 12.
[0062] The direction along which the bottom portion is folded is decided by the direction along which the recessed portion 12a and the protruded portion 12b are formed. That is, the bottom portion is folded in the direction along which the recessed portion side is folded inward, and when once folded, according to the folded habit formed to the folding line 12, it is effectively prevented for the bottom portion of the bag body 2B to return to the original shape, and the flatness (state of flatness) of the bag body 2B can be maintained, thus ensuring high performance of self-standing ability.
[0063] On the other hand, the circular-arc portions 32, 32 formed as crack-spreading prevention portion formed to both the ends of the linear portion 31 attain the function for effectively preventing the crack from being generated at or spread from the folding auxiliary portion 30.
[0064] In the case where the folding auxiliary portion 30 is formed only from the linear portion 31, when the bottom portion of the bag body 2b is folded, there is a possibility of causing the concentration of stress on the end edges of the linear portion 31 and spreading the crack therefrom. However, the formation of the circular-arc portions 32, 32 to the end edges of the linear portion 31 as in the present embodiment positively prevents the concentration of the stress on the end edge portions of the linear portion 31. Moreover, even if any crack be generated and spread from the end edges 33, 33 of the circular-arc portions 32, 32, the tangential lines 45, 45 at these portions are directed to the downward direction of the bag body 2B, so that the crack will spread downward and not spread towards the content accommodation portion 10 of the bag body 2B, thus being effective and advantageous.
[0065] In an alternation, the folding auxiliary portion 30 may have a pattern such as shown in Fig. 11, in which each of the folding auxiliary portions 30, 30 is composed of, a linear cut-out portion 31 as linearly extending cut-out formed on the folding line 12 and circular-arc portions 34, 34 as crack-spreading prevention portions formed to both ends of the linear cut-out portion 31 so as to be curved downward from both ends of the linear cut-out portion 31. These circular-arc portions 32, 32 have end edge portions 35, 35 on which tangential lines 46, 46 extend in a circumferential direction so as to cross the extension of the linear cut-out portion 31 at an angle of θ, which is an acute angle.
[0066] According to the formation of the folding auxiliary portions 30, 30 of this example, the stress concentration can be effectively prevented by the formation of such circular-arc portions 34, 34, thus preventing the cracks from being generated and spread.
[0067] Further, the folding auxiliary portion 30 is not limited to the continuous cut-out line and, as shown in Fig. 12, it may be formed as score line. In such case, the folding auxiliary portion 30 is composed of the linear portion 31a formed on the folding line 12 and circular- arc portions 36, 36 formed to both ends thereof so as to be curved in the downward direction of the bag body 2B.
[0068] In the example of Fig. 12, the positions to which the end edges 37, 37 are formed extend to portions on which tangential lines 47, 47 extend in a circumferential direction so as to cross the extension of the linear portion 31 at a right angle or an acute angle θ.
[0069] Furthermore, in the above examples, although the crack-spreading prevention portions are formed in shape of circle or like, any other shape may be adopted.
[0070] Fig. 13 shows an example of the folding auxiliary portion 30 in which a linear cut-out 38 provides a circular-arc shape having a large curvature so as to substantially accord with the position of the folding line 12. The crack-spreading prevention portions 39, 39 are formed by cutting off the bottom portion of the bag body 2B in shape of circle at both the ends of the linear cut-out 38. According to this example, substantially the same function and effect as those mentioned with reference to the above examples may be attained.
[0072] With reference to Fig. 14, the folding auxiliary portion 30 is composed of a linear cut-out 40 providing a circular-arc shape having a large curvature and the circular-arc portions formed as crack-spreading prevention portions 41, 41 formed to both end portions of the linear cut-out 40. The circular-arc portions 41, 41 are curved in an upward direction of the bag body 2B as shown with respect to the linear cut-out 40, and the distal end portions 42, 42 of the circular-arc portions 41, 41 extend in the circumferential directions till the extensions of the tangential lines at the end edge portions 42, 42 directed downward with respect to the bag body 2B.
[0073] In the above, the examples, in which the folding auxiliary portions are formed to both the flat surface portions 3, 3, are described and explained. However, according to the second embodiment of the present invention, the other examples may be further provided. For example, as shown in Figs. 15A to 15F, the folding auxiliary portion may be formed to at least one of the flat surface portions 3a, 3b and the side surface portion 4.
[0074] That is, with reference to Figs. 15B, 15C and 15E, the folding auxiliary portion 30 is formed only to one flat surface side 3a with respect to the folding line 5 formed to the side surface portion 4 with respect to the thickness direction of the bag body, and such folding auxiliary portion can attain the function of determining the folding direction of the bottom portion of the bag body. On the other hand, as shown with the example of Fig. 15d, such function may be advantageously attained by forming the folding auxiliary portions 30 to the one flat surface portion 3b and to a portion 4a of the side surface portion 4 on the other one flat surface portion side 3b with respect to the folding line 5. That is, the folding auxiliary portions 30 in this example are formed to be asymmetric with respect to the folding line 5 in the thickness direction of the bag body 2B.
[Third Embodiment 3]
[0075] The third embodiment of the gusset bag according to the present invention will be further described with reference to Fig. 16.
[0076] The gusset bag 1C of this embodiment comprises a bag body 2C composed of a pair of opposing flat portions (flat surface portions) 3, 3 and a pair of gusset-shaped side portions (side surface portions 4, 4) connected to both side edges of the flat portions 3, 3, respectively. The thus formed bag body 2C also has the upper (top) end edge to which the take-out device 20 for taking the inner content out of the gusset bag body 2C is mounted orprovided, the take-out device 20 being provided with the take-out tube 21 and the cap 22 screwed thereto. The detailed explanation of the constructional elements or portions of the gusset bag 1C of this third embodiment corresponding to those of the gusset bag 1A or 1B of the first or second embodiment are omitted herein by adding the same reference numerals.
[0077] Folding auxiliary portions 50, 50 of this third embodiment are formed to portions on the outer edge side than the inner content accommodation portion 10 of the bag body 2C on both lateral sides of the bottom portion thereof.
[0078] As shown in Figs. 16 and 17, the folding auxiliary portions 50, 50 have coarse or rough surface portions on the surface of the flat surface portions 3, 3 at positions corresponding to both the side portions 8b, 8b of the heat seal portion 8 at the bottom of the bag body 2C.
[0079] The folding (folded) line 12 is formed, as shown in Fig. 18, by placing and then pressing the bag body 2C in a die to form the recessed portion 12a on the side of the flat surface portion 3 in the direction along which the bottom portion of he bag body 2C is folded and the protruded portion 12b on the opposing side.
[0080] The coarse surface portion of each of the folding auxiliary portions 50, 50 is formed as aggregation of a number of fine holes, and as shown in Fig. 19, these holes are formed by forming a number of fine blind holes (not through holes) of a PET layer 70 outside an aluminium foil layer 71 being the barrier layer. Such folding auxiliary portion 50 will be formed, for example, by passing the film material (member) through pressing roller unit on the surface of which sand paper having a predetermined roughness is attached. In Fig. 19, reference numeral 72 is the ON layer and 73 is the CCP layer of the laminate film forming the flat surface portion of the bag body.
[0081] According to this embodiment, in which the folding auxiliary portions 50, 50 are formed as coarse or rough surface portions, the portions at which the folding auxiliary portions 50, 50 are formed are weakened in their rigidity, andhence, the bottom portion of the bag body 2C can be easily folded at these positions. Moreover, since the folding line 12 has already been formed to the portion to be folded, the bottom portion of the bag body 2C can be further easily folded by the synergistic effects of the folding line 12 and the folding auxiliary portions 50, 50.
[0082] Further, the direction along which the bottom portion is folded is determined by the direction of the formation of the recessed portion 12a and protruded portion 12 of the folding line 12. That is, the bottom portion of the bag body 2C is folded in the direction so as to accord inward folding direction of the recessed portion 12a. Once the bottom portion is folded, the bottom portion is prevented from returning to take the original shape because of folded habit and the flat condition of the bag body 2C can be maintained, thus ensuring the improved self-standing ability or performance.
[0083] In a modified example, as shown in Fig. 20, when the outer layer is formed of the evaporated PET, fine holes as folding auxiliary portions 50A, 50A may be formed so as to reach to a layer inside the outer layer or to penetrate the layer inside the outer layer. Further, in the case where the aluminium foil is used as film material, the blind or through holes forming the coarse surfaces may be formed so as to reach or penetrate the layer inside the aluminium foil layer. In such example, since the folding auxiliary portions 50A, 50A are formed to the positions outside the content accommodation portion of the gusset bag body 2C, the formation of such folding auxiliary portions never adversely influence to the inner content. In the illustrated structure of Fig. 20, reference numeral 74 denotes an evaporated PET layer, 72 denotes an ON layer and 73 is a CCP layer.
[0084] In the described third embodiment, the folding auxiliary portions are formed to both the flat surface portions 3, 3, but in modified embodiments or examples, various forms may be adopted as shown in Fig. 21A to 21F, in which the folding auxiliary portion may be formed to at least one of the flat surface portions 3a, 3b and the side surface portion 4.
[0085] That is, with reference to Figs. 21B, 21C and 21E, the folding auxiliary portion 50 is formed only to one flat surface side 3a with respect to the folding line 5 formed to the side surface portion 4 with respect to the thickness direction of the bag body, and such folding auxiliary portion can attain the function of determining the folding direction of the bottom portion of the bag body. On the other hand, as shown in the example of Fig. 21D, such functionmay be advantageously attainedby forming the folding auxiliary portions 30 to the one flat surface portion 3b and to a portion 4a of the side surface portion 4 on the other one flat surface portion side 3a with respect to the folding line 5. That is, the folding auxiliary portions 50 in this example are formed to be asymmetric with respect to the folding line 5 in the thickness direction of the bag body.
[0086] Further, in the cases where the folding auxiliary portions are formed to the film materials of both the flat surface and side surface portions 3 and 4, the surface roughing working will be effected from the outer layer side of each film material.
[0087] With reference to the first to third embodiments of the gusset bags of the present invention, there are described, hereinbefore, the folding auxiliary portions which are formed to the triangle shape portions of both side portions 8b, 8b of the heat seal portion 8 sealing the lower edge portions of the bag body, but the present invention is not limited to these embodiments, and in a modification, they may be formed to portions of both the side portions 8b, 8b corresponding to the lower end portion of the content accommodation portion 10 or portions lower than these portions.In addition,thesefolding auxiliary portions may be formed otherwise to the central portion 8a of the heat seal portion 8 or to the entire portion of the heat seal portion 8.
[0088] Furthermore, in the above embodiments, the gusset bag body is formed from a film material forming a pair of flat surface portions 3 and another film material forming a pair of side surface portions 4 which are independently formed from the flat surface portions 3 and then bonded or joined together, but in a modification, these surface portions 3 and 4 may be formed from a single film materialhavingbothsideedgeswhicharebondedorjoinedtogether.
1. A gusset bag comprising:
a pair of opposing flat surface portions;
a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, so as to provide a tubular body having openings at top and bottom end portions thereof, said side surface portions having gusset portions formed by inwardly folding the side surface portions so that the inwardly folded gusset lines are opposed to each other when the side surface portions are applied to the flat surface portions;
a bottom portion closing one end open portion of the tubular body so as to provide a gusset bag body, said the other one end open portion being provided with a take-out portion through which an inner content filling a content accommodation portion of the gusset bag body is taken out, and said other one end opened portion being tightly closed at a portion other than the take-out portion; and
a folding auxiliary portion formed to the bottom portion of the gusset bag body to a portion outside an outer end edge of the content accommodation portion of the gusset bag body for assisting folding of the bottom portion along a folding line to thereby easily provide a flat bottom surface,
wherein said folding auxiliary portion is formed as a through hole at a portion at least one of the flat surface portion and the side surface portion, said through hole being a hole elongated in a direction so as to accord with a direction along which a folding line of the bottom portion extends.2. A gusset bag comprising:
a pair of opposing flat surface portions;
a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, so as to provide a tubular body having openings at top and bottom end portions thereof, said side surface portions having gusset portions formed by inwardly folding the side surface portions so that the inwardly folded gusset lines are opposed to each other when the side surface portions are applied to the flat surface portions;
a bottom portion closing one end open portion of the tubular body so as to provide a gusset bag body, said the other one end open portion being provided with a take-out portion through which an inner content filling a content accommodation portion of the gusset bag body is taken out, and said other one end opened portion being tightly closed at a portion other than the take-out portion; and
a folding auxiliary portion formed to the bottom portion of the gusset bag body to a portion outside an outer end edge of the content accommodation portion of the gusset bag body for assisting folding of the bottom portion along a folding line to thereby easily provide a flat bottom surface,
wherein said folding auxiliary portion is formed as a recessed portion by reducing a thickness of the bottom portion of the gusset bag body.3. A gusset bag comprising:
a pair of opposing flat surface portions;
a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, so as to provide a tubular body having openings at top and bottom end portions thereof, said side surface portions having gusset portions formed by inwardly folding the side surface portions so that the inwardly folded gusset lines are opposed to each other when the side surface portions are applied to the flat surface portions;
a bottom portion closing one end open portion of the tubular body so as to provide a gusset bag body, said the other one end open portion being provided with a take-out portion through which an inner content filling a content accommodation portion of the gusset bag body is taken out, and said other one end opened portion being tightly closed at a portion other than the take-out portion; and
a folding auxiliary portion formed to the bottom portion of the gusset bag body to a portion outside an outer end edge of the content accommodation portion of the gusset bag body for assisting folding of the bottom portion along a folding line to thereby easily provide a flat bottom surface,
wherein said folding auxiliary portion is formed as a coarse surface portion composed of aggregation of a number of fine holes formed to at least one of the flat surface portion and the side surface portion.4. A gusset bag comprising:
a pair of opposing flat surface portions;
a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, so as to provide a tubular body having openings at top and bottom end portions thereof, said side surface portions having gusset portions formed by inwardly folding the side surface portions so that the inwardly folded gusset lines are opposed to each other when the side surface portions are applied to the flat surface portions;
a bottom portion closing one end open portion of the tubular body so as to provide a gusset bag body, said the other one end open portion being provided with a take-out portion through which an inner content filling a content accommodation portion of the gusset bag body is taken out, and said other one end opened portion being tightly closed at a portion other than the take-out portion; and
a folding auxiliary portion formed to the bottom portion of the gusset bag body to a portion outside an outer end edge of the content accommodation portion of the gusset bag body for assisting folding of the bottom portion along a folding line to thereby easily provide a flat bottom surface,
wherein said folding auxiliary portion is formed to at least one of the flat surface portion and the side surface portion and is composed of a linear cut-out formed so as to extend in a width direction of the gusset bag body and a crack-spreading prevention portions formed to both end portions of the linear cut-out.5. The gusset bag according to any one of claims 1 to 4, wherein said folding auxiliary
portion is formed to at least one of the flat surface portion and the side surface
portion positioned on one side in the thickness direction of the gusset bag body with
the folding line formed to the side surface portion being boundary thereof.
6. The gusset bag according to any one of claims 1 to 4, wherein said folding auxiliary
portion is formed to one of the flat surface portion and to a portion of the side
surface portion on the other side flat surface portion side from the folding line
formed to the central portion of the side surface portion.
7. The gusset bag according to any one of claims 1 to 4, wherein said bottom portion
has a portion positioned inside the folding line when the bottom portion is folded
and the folded line having a recessed shape is overlapped with the folding auxiliary
portion at the folding auxiliary portion forming portion.
8. The gusset bag according to any one of claims 1 to 4, wherein said take-out portion
comprises a take-out tube and a cap engaged with the take-out tube, said take-out
tube having one end inserted into the bag body and another end projecting outward
therefrom, and the take-out tube is clamped between the upper edge portions of the
flat surface portions and then tightly sealed thereto at a peripheral portion thereof.
9. The gusset bag according to claim 2, wherein said recessed portion is formed in a
manner that a through hole is formed to the side surface portion and the through hole
is then covered up by bonding the flat surface portion to the side surface portion.
10. The gusset bag according to claim 4, wherein each of said crack-spreading prevention
portions is a circular-arc cut out continuous to the end portion of the linear cut-out.
11. A gusset bag which comprises a pair of opposing flat surface portions and a pair of
side surface portions connected, at side edge portions thereof, to side edge portions
of the flatsurface portions,respectively,through a fusing treatment so as to provide
a tubular body having openings at top and bottom end portions thereof, said side surface
portions having gusset portions formed by inwardly folding the side surface portions,
and in which inner surfaces of the flat surface portions and the side surface portions
are fused so that the fused side portions of the flat and side surface portions of
the tubular body and the fused bottom portion thereof are connected to thereby form
triangular heat-seal portions,
wherein a folding auxiliary portion for assisting folding of the bottom portion of the tubular body to thereby easily forma flat portion to the bottom portion to the heat-seal portion at which one of the triangular heat-seal portions formed by fusing at least one of the flat and side surface portions, and said folding auxiliary portion comprises at least one score line, which is composed of a linear portion formed to accord with a position to which a folding line along which the bottom portion of the gusset bag body is folded and circular-arc portions formed at both ends of the linear portion.
wherein a folding auxiliary portion for assisting folding of the bottom portion of the tubular body to thereby easily forma flat portion to the bottom portion to the heat-seal portion at which one of the triangular heat-seal portions formed by fusing at least one of the flat and side surface portions, and said folding auxiliary portion comprises at least one score line, which is composed of a linear portion formed to accord with a position to which a folding line along which the bottom portion of the gusset bag body is folded and circular-arc portions formed at both ends of the linear portion.
12. A gusset bag which comprises a pair of opposing flat surface portions and a pair of
side surface portions connected, at side edge portions thereof, to side edge portions
of the flat surface portions, respectively, through a heat-seal treatment so as to
provide a tubular body having openings at top and bottom end portions thereof, said
side surface portions having gusset portions formed by inwardly folding the side surface
portions, and in which inner surfaces of the flat surface portions and the side surface
portions are heat-sealed so that the heat-sealed side portions of the flat and side
surface portions of the tubular body and the heat-sealed bottom portion thereof are
connected to thereby form triangular heat-seal portions,
wherein a folding auxiliary portion for assisting folding of the bottom portion of the tubular body to thereby easily forma flat portion to the bottom portion to the heat-seal portion at which one of the triangular heat-seal portions formed by heat-sealing at least one of the flat and side surface portions, and said folding auxiliary portion comprises a through hole formed to the side surface portion of the tubular body and the through hole is a hole elongated in a direction so as to accord with a direction along which a folding line of the bottom portion extends so that the folding auxiliary portion is covered up by the flat surface portion.
wherein a folding auxiliary portion for assisting folding of the bottom portion of the tubular body to thereby easily forma flat portion to the bottom portion to the heat-seal portion at which one of the triangular heat-seal portions formed by heat-sealing at least one of the flat and side surface portions, and said folding auxiliary portion comprises a through hole formed to the side surface portion of the tubular body and the through hole is a hole elongated in a direction so as to accord with a direction along which a folding line of the bottom portion extends so that the folding auxiliary portion is covered up by the flat surface portion.
13. A gusset bag comprising:
a pair of opposing flat surface portions;
a pair of side surface portions connected, at side edge portions thereof, to side edge portions of the flat surface portions, respectively, so as to provide a tubular body having openings at top and bottom end portions thereof, said side surface portions having gusset portions formed by inwardly folding the side surface portions so that the inwardly folded gusset lines are opposed to each other when the side surface portions are applied to the flat surface portions;
a bottom portion closing one end opened portion of the tubular body so as to provide a gusset bag body;
a take-out portion provided for the other one end open portion of the bag body through which an inner content in a content accommodation portion of the gusset bag body is taken out; and
a folding auxiliary portion formed to the bottom portion of the gusset bag body to a portion outside an outer end edge of the content accommodation portion of the gusset bag body for assisting folding of the bottom portion along a folding line to thereby easily provide a flat bottom surface.