JP2023036556A - Storage bag and method of producing the same - Google Patents

Abstract

To provide a storage bag allowed to inhibit the occurrence of a fracture or pinhole in a resin film at a resin-rich area as a start point, in a junction between a resin film and a welded portion of a discharge member of the storage bag.SOLUTION: A storage bag comprises a bag body that has an accommodation space to receive a content stored inside a heat-sealed portion of resin films superposed together and a discharge member that has a welded portion having a side face welded to the resin films and a cylindrical discharge portion protruding in one, predetermined direction from one end in the predetermined direction of the welded portion and is formed with a communication conduit passing through the welded and discharge portions so that the content stored can be discharged externally of the bag body from the accommodation space. The welded portion is formed with the resin-rich area over an entire periphery of a bottom peripheral edge of the welded portion.SELECTED DRAWING: Figure 1

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage bag provided with a discharge member for discharging a stored substance in a bag body for storing a stored substance, and a method for manufacturing the storage bag.

A storage bag for storing a medical drug solution, an infusion solution, a cell agent solution, etc. is composed of, for example, a bag main body made of a flexible resin film for storing the stored material, and a hard discharge member welded to the bag main body for discharging the stored material. and Since the discharge member must be firmly welded to the resin sheet so as not to leak the stored material, for example, a discharge member having a substantially boat-shaped welded portion to be welded to the resin film is used. be done.

Here, a conventional storage bag will be described. FIG. 7(a) is a plan view showing a conventional storage bag, and FIG. 7(b) is a view taken along line EE shown in FIG. 7(a). As shown in FIG. 7(a), a conventional storage bag 1 is made by superimposing flexible resin films 3 and joining the superimposed sides together by thermal fusion (heat sealing) to form a heat-sealed portion 5. to form At this time, a part of the overlapping sides is not welded, but is used as a gap (opening) for fixing the ejection member 4 . Then, the resin film 3 and the ejection member 4 are heat-sealed with a mold or the like in a state in which the portion to be welded of the ejection member 4 is fitted in the opening of the resin film 3 formed in a bag shape by the heat seal portion 5 . It is known to create a storage bag 1 in which a storage space for storing a stored material is formed by joining the overlapping portions of the welded portions.

JP 2017-178371

By the way, it is known that in the above-described conventional storage bag, when the resin film and the ejection member are heat-sealed, a phenomenon called "resin pool" occurs in which the resin melted from both protrudes from the welding range and solidifies. It is In the storage bag 1 shown in FIGS. 7(a) and 7(b), a resin puddle 7 is formed in a portion of the housing space side of the joint 6 between the resin film 3 and the portion to be welded of the discharge member 4. .

When the resin film in the vicinity of the welded portion is spread out due to factors such as external force being applied when the storage bag is used, stress concentrates on the resin pool, and there is a risk of breaking the resin film. In addition, the resin pool may be peeled off from the resin film and cause a pinhole or the like due to the resin film in the vicinity of the portion to be welded being pushed out due to factors such as an increase in internal pressure.

The present invention has been made in view of such problems, and suppresses the occurrence of breakage of the resin film and pinholes originating from the resin pool at the joint between the resin film of the storage bag and the welded portion of the discharge member. An object of the present invention is to provide a storage bag that can be used.

The inventors of the present invention have conducted intensive studies on how to suppress breakage of the resin film and pinholes that occur starting from the resin puddle at the joint between the resin film of the storage bag and the welded portion of the discharge member. Instead of forming a resin pool only on a part of the bottom surface of the welding part on the accommodation space side at the joint part between the resin film and the welding part of the ejection member, The inventors have found that by forming a resin pool along the entire periphery of the bottom surface of the welded portion on the accommodation space side, it is possible to suppress breakage of the resin film, pinholes, etc., and have completed the present invention.

According to the invention,
(1) A bag body having a storage space for storing a stored material inside a heat-sealed portion of overlapping resin films, a portion to be welded whose side surface is welded to the resin film, and a predetermined and a cylindrical discharge portion protruding in one direction, and a communicating passage passing through the welding portion and the discharge portion is formed so that the stored material can be discharged from the accommodation space to the outside of the bag body. and a port, wherein a resin pool is formed along the entire periphery of the bottom surface of the portion to be welded,
(2) The storage bag according to (1) is provided, wherein the welded portion has a substantially rhomboid bottom surface,
(3) The storage bag according to (1) or (2) is provided, characterized in that the height of the resin pool protruding from the bottom surface of the welded portion is 100 μm or more,
(4) In the storage bag manufacturing method described in (1) to (3), the port is supplied between the overlapping resin films to heat the side surface of the portion to be welded and the resin film. A method for manufacturing a storage bag is provided, characterized in that the portion to be welded is welded to the resin film by heating using a mold,
(5) The method for manufacturing a storage bag according to (4) is provided, characterized in that the welded portion has a protruding portion extending toward the accommodation space over the entire periphery of the bottom surface,
(6) The method for manufacturing a storage bag according to (4), wherein the welded portion has a protruding portion extending outward over the entire circumference at the end of the side surface on the accommodation space side. provided.

In the storage bag of the present invention, a resin pool is formed along the entire peripheral edge of the bottom surface of the welded portion on the housing space side at the joint portion between the resin film and the welded portion of the discharge member. When the resin film near the part to be welded is spread due to factors such as the application of an external force, even if stress is locally concentrated on the resin pool, the peel strength is improved by the resin pool, so the resin film It is possible to suppress the breakage of and the occurrence of pinholes.

(a) It is a front view of the storage bag which concerns on one Embodiment of this invention. (b) A cross-sectional view taken along the line AA shown in FIG. 1(a). (c) A cross-sectional view taken along line BB shown in FIG. 1(a). (d) is a modification of the cross-sectional view taken along the line BB shown in FIG. 1(a). 1 is a perspective view of a port according to one embodiment of the invention; FIG. (a) A plan view of a port according to an embodiment of the present invention. (b) A front view of a port according to an embodiment of the present invention. (c) A bottom view of a port according to an embodiment of the present invention. (d) A side view of a port according to an embodiment of the present invention. (a) It is a front view of a port according to another embodiment of the present invention. (b) A bottom view of a port according to another embodiment of the present invention. (c) A side view of a port according to another embodiment of the present invention. 4(d) is a cross-sectional view taken along line CC shown in FIG. 4(a). (a) It is a front view of a port according to another embodiment of the present invention. (b) A bottom view of a port according to another embodiment of the present invention. (c) A side view of a port according to another embodiment of the present invention. (d) is a cross-sectional view taken along line DD shown in FIG. 5(a); FIG. 4 is a bottom view of the port showing the measurement points of the height of the resin puddle in the embodiment of the present invention; (a) It is a front view concerning the conventional storage bag. (b) A cross-sectional view taken along the line EE shown in FIG. 7(a).

The present invention will be described in detail below. It should be noted that the present invention is not limited to the following forms, and various forms are possible within the scope of the effects of the present invention.

FIG. 1(a) is a front view of a storage bag according to one embodiment of the present invention. As shown in FIG. 1(a), the storage bag 1 of the present invention has heat seal portions 5 (a top seal portion 5a, a bottom seal portion 5b, and a pair of side seal portions 5c) of overlapping resin films 3. It has a bag body 2 having a storage space for storing the stored material and a welded portion 4b fixed to the heat-sealed portion 5 (top seal portion 5a), and the stored material flows into or out of the bag body from the storage space. A welded portion 4b of the port is joined to the resin film 3 above the bag body 2 so that the stored material can flow in or out. As shown in FIGS. 1(a), 1(b) and 1(c), the storage bag of the present invention has a storage space at the joint 6 between the resin film 3 and the welded portion 4b of the port. A resin pool 7 is formed along the entire periphery of the bottom surface 4c of the welded portion on the side.

In the present invention, instead of forming a resin pool only on a portion of the bottom surface 4c of the welding portion on the accommodation space side at the joint portion 6 between the resin film 3 and the welding portion 4b of the port, By forming the resin pool 7 along the entire periphery of the bottom surface 4c of the welding portion on the accommodation space side at the joint portion 6 with the welding portion 4b, breakage of the resin film 3, pinholes, and the like can be suppressed. Although the reason for this is not clear, by forming the resin reservoir 7 substantially uniformly along the entire periphery of the bottom surface 4c of the welded portion 4b, the welded portion 4b may be damaged by factors such as external force being applied during use of the storage bag. Even if the stress when the nearby resin film 3 is spread is locally concentrated on a part of the resin puddle 7, it is presumed that the peel strength is improved by the resin puddle.

The amount and shape of the resin pool 7 formed around the bottom surface 4c of the welded portion of the port may be appropriately adjusted within the scope of the present invention, and are not particularly limited. ), as shown in FIGS. 1(b) and 1(c), the resin reservoir 7 may be formed so as to protrude from the bottom surface 4c of the welded portion of the port toward the accommodation space along the entire periphery of the bottom surface. . The height of the resin pool protruding from the bottom surface 4c of the welded portion of the port is not particularly limited, but for example, the lower limit is 100 μm or more, preferably 200 μm or more, more preferably 300 μm or more, and particularly preferably 500 μm or more. , most preferably 700 μm or more, and the upper limit is 3000 μm or less, preferably 2500 μm or less, more preferably 2250 μm or less, still more preferably 2000 μm or less, particularly preferably 1700 μm or less, most preferably 1500 μm or less. In addition, the height of the resin pool protruding from the bottom surface 4c of the welded portion of the port is preferably substantially uniform over the entire periphery of the bottom surface. It is preferably within 3 times the average height, more preferably within 2 times, even more preferably within 1.5 times. If the height of the resin puddle protruding from the bottom surface 4c of the welded portion of the port is within the above range, there will be no breakage, pinholes, etc. in the resin film near the junction between the resin film 3 of the storage bag and the welded portion 4b of the port. can be suppressed. In addition, as shown in FIG. 1(d), the resin film 3 on the storage space side at the joint 6 between the resin film 3 and the welded portion 4b of the port is in a state of entering toward the inside of the storage bag 1. There may be.

The bag body 2 is formed, for example, in a rectangular shape when viewed from the front. The bag body 2 is formed by stacking or folding one or more flexible resin films 3 and forming a bag shape by heat-sealing predetermined portions (upper, lower, left, and right sides). It has seal portions (a top seal portion 5a, a bottom seal portion 5b, and a pair of side seal portions 5c). In addition, the bag body may be closed so that four sides (top, bottom, left, and right) form a bag, and the number of sides of the heat-sealed portion 5 is not limited to four or less.

Inside the bag main body 2, that is, inside the heat-sealed portion 5, a storage space having a capacity capable of storing a predetermined amount of stored material is formed. The volume of the storage space may be appropriately designed according to the type and application of the stored material. Further, the bag body 2 may be provided with gussets for securing volume on the bottom seal portion 5b side or the side seal portion 5c side.

The material constituting the resin film 3 of the bag body 2 is not particularly limited. Examples include thermoplastic resins such as vinyl alcohol copolymer resins, ethylene-vinyl acetate copolymer resins, polyester resins, nylon resins, polyvinyl chloride, and polystyrene. The resin film may be a film formed by blending different resins or a laminate of films of a plurality of resin materials.

FIG. 2 is a perspective view of a port according to one embodiment of the present invention, and FIG. 3 is (a) plan view, (b) front view, and (c) bottom view of the port according to one embodiment of the port of the present invention. , (d) is a side view. As shown in FIGS. 2 and 3, the port 4 is inserted between the two resin films 3 and has a weldable portion 4b configured so that the side surface can be welded to the resin film 3, and a medical tube or the like. and a tubular discharge portion 4a protruding in one predetermined direction from one end of the welding portion to be welded. A communicating passage 4d for inflow or outflow of the stored matter is formed through the reservoir.

As shown in FIGS. 2 and 3, the welded portion 4b of the port has a long axis along the extending direction of the top seal portion 5a and a longitudinal axis extending in a direction orthogonal to the extending direction in plan view and bottom view. A bottom surface 4c is formed in a substantially rhombic shape having a minor axis. The welded portion 4b is a portion whose side surfaces can be welded to the resin film 3 over a wide range along the direction of the top seal portion 5a. In addition, the welded portion 4b has a sufficient thickness in the axial direction of the port (or in the extending direction of the communication path) in a front view, and has a substantially boat-shaped overall appearance. The shape of the welding part is not limited to this. It may have a substantially cylindrical appearance as a general appearance, or may have a substantially polygonal bottom surface such as a quadrangle and have a substantially prismatic overall appearance.

The material forming the port 4 is not particularly limited, but it is preferable to use a resin material that is harder than the material forming the bag body 2 . Examples of materials constituting the port 4 include polyethylene-based resins such as linear low-density polyethylene, low-density polyethylene, and high-density polyethylene, polypropylene-based resins, ethylene-vinyl alcohol copolymer resins, and ethylene-vinyl acetate copolymer resins. Thermoplastic resins such as polymer resins, polyester-based resins, nylon-based resins, polyvinyl chloride, and polystyrene can be used, and one or two or more selected from these can be used. The material constituting the port 4 is preferably a material having a melting point close to the melting point of the resin film 3. It is preferably 10°C or less. In addition, the MFR (measured according to JIS-K7210) of the material constituting the port 4 is not particularly limited, but for example, the lower limit is 5 g/10 min or more, 10 g/min or more, 15 g/min or more, It is 20 g/min or more, and the upper limit is 50 g/min or less, 30 g/min or less, and 25 g/min or less. In the present invention, the melting point and MFR of the material forming the port and the resin film may be appropriately adjusted for design, and the resin pool may be formed along the entire periphery of the bottom surface of the portion to be welded.

Next, a method for manufacturing the storage bag of the present invention will be described. The method for manufacturing the storage bag of the present invention can employ a conventionally known method and is not particularly limited. a bag forming step for forming a main body; an inserting step for inserting a welded portion of a port into an opening defined by a welding region; and a welded portion of the port inserted into the opening and a resin film around the welded portion. and a heating step of fusing the welded portion to the resin film by heating using a heating mold.

In the bag forming step, two flexible resin films are overlapped, or one flexible resin film is folded, and a portion of the peripheral edge of the overlapped resin film is heat-sealed. As a result, as shown in the region surrounded by the dashed line in FIG. 1, the band-shaped welding regions (top seal portion, bottom seal portion, pair of side seal portions) in which the superimposed resin sheets are welded to each other, and the resin film A bag body is formed having an opening (not shown) where the are not welded together. The area surrounded by the welding area becomes the accommodation space.

In the port insertion step, the welded portion of the port is inserted into the opening defined by the welded region. When inserting a plurality of ports into the opening, the ports are inserted at predetermined intervals. The number of ports inserted into the opening is not particularly limited. In addition, after the port insertion process, the resin film near the joint and the welded part of the port are heated in order to increase the fluidity of the resin in the resin film and the welded part of the port in the heating process and make it easier to form a resin pool. - A preheating process for raising the temperature may be provided.

In the heating step, the portion to be welded of the port inserted into the opening and the resin film on the periphery of the portion to be welded are heated using a heating mold to weld the portion to be welded to the resin film. As a result, the portion to be welded can be reliably welded to the resin film, and as a result, at least the inside of the accommodation space can be sealed liquid-tight. The heating process may be performed in multiple stages while changing the heating temperature of the heating mold, the heating time, the clearance between the heating mold and the portion to be welded of the port, the pressing force by the heating mold, and the like. The shape and material of the heating mold are not particularly limited. good. The heating mold, for example, can be heated by a built-in heater composed of a heating wire, or can be heated by passing an electric current through the heating mold (impulse seal method). Just do it.

After the heating step, a cooling step may be provided to solidify the molten resin at the joint. In the cooling step, for example, the molten resin can be solidified by cooling using a pair of vertically symmetrical cooling dies each having a concave portion corresponding to the shape (substantially boat-shaped) of the welded portion of the port. . It is sufficient that a cooling medium flows inside each of the cooling molds so that they can be cooled.

The method of forming a resin pool along the entire periphery of the bottom surface of the welded portion is not particularly limited. The clearance between the heated mold and the welded part of the port, the heating temperature of the heated mold, the heating time, the pressing force of the heated mold, etc. are appropriately adjusted, and the cooling to solidify the molten resin at the joint In the process, it can be achieved by appropriately adjusting the shape of the cooling mold, the clearance between the cooling mold and the portion to be welded of the port, the cooling temperature of the cooling mold, the cooling time, the pressing force of the cooling mold, etc. . At that time, the material of the resin film and the port may be appropriately adjusted in consideration of the fluidity of the molten resin in the heating process and the cooling process.

The shape of the welded portion of the port may be changed in order to form a resin pool along the entire periphery of the bottom surface of the welded portion. 4 and 5 are diagrams of other embodiments of the port of the present invention. As shown in FIG. 4, the welded portion 41b of the port may have a protruding portion 41e extending toward the housing space over the entire periphery of the bottom surface. 42b may be configured to have a protruding portion 42e extending outward over the entire circumference at the end of the side surface on the accommodation space side. If the shape of the welded portion of the port is as described above, the projecting portion of the welded portion melts in the heating process for welding the welded portion and the resin film, and the resin pools around the entire periphery of the bottom surface of the welded portion of the port. can be formed.

(Examples 1 to 3 and Comparative Example 1)
A port made of a linear low-density polyethylene film (melting point 127° C.) with a thickness of 0.15 mm and a high-density polyethylene (melting point 129° C.) shown in FIG. CC' distance) and a short axis of 10 mm (AA' distance shown in FIG. 6)), and the bag forming process, port insertion process, heating process and cooling process are performed in the same manner as the manufacturing method described above. After that, a storage bag was manufactured. Table 1 shows the manufacturing conditions in the heating process and the cooling process.

The following measurements and evaluations were performed on the obtained samples of Examples and Comparative Examples. Table 2 shows the results.
[Resin puddle height measurement]
Port welding parts are cut out from the storage bag obtained above, and shown in FIG. '), and a laser microscope (manufactured by KEYENCE CORPORATION, shape analysis Using a laser microscope (VK-X1000), the height (μm) of the resin puddle protruding from the bottom surface of the welding part was measured. The number of measurements was set to n=3, and the average value was described.
[Leak evaluation]
A leak test was performed on the storage bag obtained above by a pressurized standing method. The test pressure was set to 30 kPa, and was held for 90 seconds from the time the test pressure was reached, and the presence or absence of leakage was evaluated. Evaluation criteria are as follows.
○: No leak occurred ×: The film was broken at the periphery of the bottom surface of the welded part, and a leak occurred.

As shown in Table 1, the storage bags of Examples 1 to 3, in which a substantially uniform resin pool was formed along the entire periphery of the bottom surface of the welded portion of the port, had a film thickness at the bottom edge of the welded portion in the leak evaluation. No rupture was observed. On the other hand, in the storage bag of Comparative Example 1 in which a resin pool was partially formed on the periphery of the bottom surface of the welded portion of the port, the film was broken at the periphery of the bottom surface of the welded portion in the leakage evaluation, and leakage occurred.

As described above, in the storage bag of the present invention, a resin pool is formed along the entire peripheral edge of the bottom surface of the welded portion on the housing space side at the joint portion between the resin film and the welded portion of the discharge member. It can suppress breakage, pinholes, etc., and can be suitably used as a storage bag for medical drug solutions, infusion solutions, cell agent solutions, etc., and a cell culture bag.

1: storage bag 2: bag body 3: resin film 4; port (discharge member)
4a, 41a, 42a: discharge portions 4b, 41b, 42b: welded portions 4c, 41c, 42c: bottom surfaces 4d, 41d, 42d: communicating passages 41e, 42e: projecting portion 5: heat seal portion 5a: top seal portion 5b: Bottom seal portion 5c: Side seal portion 6: Joint portion 7: Resin reservoir

Claims (6)

A bag body having a storage space for storing a stored material inside heat-sealed portions of overlapping resin films, a welding portion having a side surface welded to the resin film, and a predetermined direction from one end of the welding portion to a predetermined direction. a port having a protruding cylindrical discharge portion, a communication passage passing through the welding portion and the discharge portion being formed, and capable of discharging the stored material from the accommodation space to the outside of the bag body; A storage bag comprising
A storage bag, wherein a resin reservoir is formed along the entire periphery of the bottom surface of the welded portion. 2. The storage bag according to claim 1, wherein the welded portion has a substantially rhomboidal bottom surface. 2. The storage bag according to claim 1, wherein the height of said resin reservoir protruding from the bottom surface of said welded portion is 100 [mu]m or more. A method for manufacturing the storage bag according to any one of claims 1 to 3,
The port is supplied between the overlapping resin films, and the side surface of the welding part and the resin film are heated using a heating mold to weld the welding part to the resin film. A method for manufacturing a storage bag. 5. The method of manufacturing a storage bag according to claim 4, wherein the portion to be welded has a protruding portion extending toward the housing space along the entire periphery of the bottom surface. 5. The method of manufacturing a storage bag according to claim 4, wherein the welded portion has a protruding portion extending outward over the entire circumference at the end portion of the side surface on the accommodation space side.

Images