JP5405496B2 - Standing bag manufacturing method and standing bag - Google Patents

Description

  The present invention relates to a standing bag suitable for a medical infusion bag and the like, and more particularly, to an improvement in a method for manufacturing the standing bag from an inflation sheet into a gusset shape.

  The standing bag can be handled in an upright position, and when used as an infusion bag, it is advantageous in that it is easy to perform mixed injection operations and the like and is efficient in transportation. There has been proposed a method of manufacturing a standing bag by forming it into a gusset shape from an inflation sheet (Patent Documents 1 and 2). According to this method, the tubular sheet formed by inflation is folded into a gusset shape (inward cross section V shape) on both sides, and the flattened sheet facing surface is welded and cut along the bag outline to cut the standing bag. Cut out. That is, in the gusset shape portion, a gusset is formed inside the welded portion, and this portion can be used as the bottom surface of the standing bag. The inside of the cylindrical sheet is not exposed directly to the outside air due to the principle of the inflation method of forming molten resin into a cylinder from the annular extrusion port under the internal gas pressure. It is a free environment and is particularly suitable for applications such as medical infusion bags. In other words, the infusion bag is not required to be completely sterilized because it is sterilized in the subsequent process against bacteria, but since the contents liquid directly enters, dust-free is an essential condition, and the method according to the above patent satisfies this condition. ing.

When implementing a method for manufacturing a standing bag from an inflation sheet by forming it into a gusset shape, it is important how to accurately and surely form the gusset shape. However, in Patent Document 1, a tubular sheet is passed through a pinch roller. There is no description in the specific method only by performing gusseting between front and rear or between the pinch roller and the winder. In Patent Document 2, both sides of a sheet are folded into a gusset shape by plate-like folding tools positioned on both sides of a cylindrical sheet sandwiched between guide plates while being flattened by a pair of tapered guide plates.
JP-A-9-174719 Japanese Patent Laid-Open No. 11-130091

  In the prior art, the blown tubular sheet is drawn upward from the die, and therefore the tubular sheet has to be cooled by air cooling. Air cooling has a simple cooling device, but the cooling efficiency is not good, so a thick sheet that exceeds 150 μm at the thinnest, such as for medical infusion bags, requires a long cooling space. was there. Also, with thick sheets exceeding 150 μm, the difference in thickness at the center of the sheet, which has only two layers with respect to both ends of the four sheets when the sheet is folded into a gusset shape, cannot be ignored. With the gap remaining in the center, blow air leaked to the downstream side, the close contact of the sheet facing surface could not be obtained, and winding into a roll shape was likely to be difficult. Further, the gusset shape is obtained by a folding tool arranged on the outer side of the tubular sheet formed by inflation. The inflation sheet secures a cylindrical shape by an internal molding pressure, and has an idea of obtaining a gusset shape while maintaining a balance with the internal molding pressure by engaging a folded portion from the outside. However, since the sheet only maintains the cylindrical shape by the internal pressure and has almost no rigidity, it is quite difficult to obtain the desired gusset shape only by folding from the outside.

  This invention has been made in view of the above problems, can be efficiently cooled, can be wound to the desired roll shape of a sheet formed into a gusset shape, And it aims at making it possible to shape | mold an inflated cylindrical sheet | seat more reliably in the expected gusset shape.

  According to this invention, the step of inflation-molding the tubular sheet, the step of forming the sheet-like shape while folding both longitudinal ends of the tubular sheet after the inflation molding into a gusset shape, and winding it on a roll, the tubular sheet Forming a first welded portion along the longitudinal direction of the sheet that serves as a bottom seal of each standing bag by welding the opposing sheet surfaces at a predetermined width from the upper and lower folding edges of the gusset-shaped portions on both sides of Second welding along the sheet width direction that serves as a side seal of each standing bag by welding the upper and lower opposing sheet surfaces of the cylindrical sheet at a predetermined width at predetermined intervals in the longitudinal direction of the transferred cylindrical sheet And forming the upper and lower opposing sheet surfaces of the cylindrical sheet along the longitudinal direction at the intermediate portion in the sheet width direction. Comprising the steps of dot and forming a cutting portion comprising an opening of each standing bag cut the sheet along the sheet width direction at the intermediate in the second welded portion. According to the present invention, in the inflation molding of the tubular sheet, the pulling out from the inflation molding die is performed downward, and the cooling of the pulled-out tubular sheet is performed by cooling the cooling water by contact cooling at the upper part from the molding part to the gusset shape. Is done. The amount of cooling water can be controlled so that the cooling water flows down to the portion of the sheet being formed into a gusset shape.

  According to the present invention, a step of blow-molding a tubular sheet, a step of forming both sides in the longitudinal direction of the tubular sheet after inflation forming into a sheet shape while folding it into a gusset shape, and winding it on a roll; Forming a first welded portion along the longitudinal direction of the sheet that serves as a bottom seal of each standing bag by welding the opposing sheet surfaces at a predetermined width from the upper and lower folding edges of the gusset-shaped portions on both sides of Forming a second welded portion along the sheet width direction that serves as a side seal of each standing bag by welding the upper and lower opposing sheet surfaces of the tubular sheet at a predetermined interval at predetermined intervals in the longitudinal direction of the cylindrical sheet And a process of cutting the upper and lower opposing sheet surfaces of the cylindrical sheet along the longitudinal direction at the intermediate portion in the sheet width direction And a step of cutting the sheet along the sheet width direction in the middle of the second welded portion to form a cut portion that becomes an opening of each standing bag, and facing the sheet when folded into a gusset shape There is provided a method for manufacturing a standing bag, characterized in that blow air to the downstream side is blocked by bringing the surfaces into close contact with each other. The adhesion of the sheet facing surface is preferably performed so as to obtain a peel strength of 0.5 to 30 g / 15 mm, preferably 1.0 to 15 g / 15 mm. A nip roller composed of an elastic roller or a stepped roller can be employed as means for closely contacting the sheet facing surface. In addition, the contact width may be the whole surface or part of the surface, especially in the gusset part, since the rebound of the folded part is strong, the close contact including the surface layer is important. If so, the effect of preventing the collapse of the gusset portion can be exhibited by the zipper effect.

  According to the present invention, a step of blow-molding a tubular sheet, a step of forming both sides in the longitudinal direction of the tubular sheet after inflation forming into a sheet shape while folding it into a gusset shape, and winding it on a roll; Forming a first welded portion along the longitudinal direction of the sheet that serves as a bottom seal of each standing bag by welding the opposing sheet surfaces at a predetermined width from the upper and lower folding edges of the gusset-shaped portions on both sides of Forming a second welded portion along the sheet width direction that serves as a side seal of each standing bag by welding the upper and lower opposing sheet surfaces of the tubular sheet at a predetermined interval at predetermined intervals in the longitudinal direction of the cylindrical sheet And a process of cutting the upper and lower opposing sheet surfaces of the cylindrical sheet along the longitudinal direction at the intermediate portion in the sheet width direction And a step of cutting the sheet along the sheet width direction in the middle of the second welded portion to form a cut portion that becomes an opening portion of each standing bag, and at the time of inflation molding of the tubular sheet, There is provided a method for manufacturing a standing bag, characterized in that a portion of a cylindrical sheet that becomes a folded portion in the shape is formed to be thin.

  When forming both sides of the tubular sheet into a gusset shape, the V-shaped section is formed at the outer periphery of the tubular sheet, and is engaged with the thin portion of the tubular sheet by a line from the outside. Each thin wall is formed by a molding apparatus including a first guide and a second guide that molds a plane portion folded from a V-shaped section in a gusset shape by engaging the first guide with a surface from outside. It is possible to guide and guide the reliable folding of the cylindrical sheet at the section.

The thin portion can be formed such that the thickness of the cylindrical sheet in the thin portion is ¼ to ¾ of the total thickness of the sheet.
In order to form a thin portion in the tubular sheet, a discharge port having a ring-shaped cross section in the inflation molding die is provided, and a protrusion is formed on the inner periphery of the discharge port at a portion corresponding to the thin portion of the tubular sheet.

  The blow-up ratio at the time of inflation molding is set to 0.7 to 1.4. Although this blow-up ratio is smaller than the value in normal inflation, the inflation pressure is suppressed to a low pressure, and it can be easily and surely folded into the desired gusset shape when used in combination with a gusset molding apparatus.

  The standing bag according to the method of the present invention welds and cuts the flattened sheet-facing surface along the bag outline while forming both sides of the tubular sheet after inflation molding into a gusset shape. The part of the cylindrical sheet which becomes the folding part in the gusset shape is thinner than the remaining part.

  The standing bag manufactured by the method for manufacturing a standing bag according to the present invention can be a sealed infusion standing bag having a rubber stopper mixed injection port attached to a bag body.

  By pulling down from the inflation molding die downwards and cooling it with water, it is possible to sufficiently cool a thick sheet exceeding 150 μm or a shortened cooling length. It can be made to flow down to a gusset molding part, and can contribute to smooth gusset molding by smoothing.

  Regardless of the level difference between the 4 layer part at the both ends in the sheet width direction and the center 2 layer part after gusset molding, the blown air to the downstream can be blocked by the adhesion (tacking) of the facing layer, and the tube is thick. Even after gusset molding from the sheet, the opposing surface is kept in close contact with the sheet, and in the gusset part, not only the inner layer but also the surface layer part is the inner surface, so the adhesion of the surface layer is also related, and the gusset fold part is In order to prevent the guide rolls from being bent or inverted by the guide rolls in the middle, the rolls can be wound on the rolls.

  In addition, the tubular sheet can be easily and surely formed into an intended shape in the gusset forming step by thinning the portion of the tubular sheet that becomes a folded portion in the gusset shape during inflation forming.

FIG. 1 is a schematic view of an apparatus for inflation molding of a cylindrical sheet according to the present invention. 2 is a schematic longitudinal sectional view of a die in the inflation molding apparatus of FIG. FIG. 3 is a schematic cross-sectional view of the discharge port in the die. FIG. 4 is a schematic view of an overflow type water cooling apparatus in the inflation apparatus. FIG. 5 is a schematic longitudinal sectional view of the gusset shape forming apparatus in FIG. 1 (cross-sectional view taken along the line VV in FIG. 1). FIG. 6 is a cross-sectional view illustrating a stage of forming a gusset shape from a cylindrical sheet by the gusset shape forming apparatus of FIG. FIG. 7 is a side view of a gusset shape forming apparatus according to another embodiment. FIG. 8 is a vertical cross-sectional view (cross-sectional view taken along line VIII-VIII in FIG. 7) of the gusset shape forming apparatus in the embodiment of FIG. FIG. 9 is a cross-sectional view (cross-sectional view taken along the line IX-IX in FIG. 7) of the gusset shape forming apparatus in the embodiment of FIG. FIG. 10 is a diagram schematically showing a cross-sectional shape of a sheet that has been gusset folded. FIG. 11 is a diagram schematically showing the cross-sectional shape of a roller in another embodiment in comparison with the cross-sectional shape of a sheet that has been gusset folded. FIG. 12 is a schematic side view of a standing bag manufacturing apparatus as a standing bag from the roll of sheet-like material of the cylindrical sheet of FIG. 13 is a schematic plan view of the standing bag manufacturing apparatus of FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 15 is a cross-sectional view of only the cylindrical sheet after welding by the sealing device of FIG. FIG. 16 is a schematic perspective view of the standing bag when the bag making process is completed.

[Inflation molding of cylindrical sheet]
FIG. 1 is an overall schematic view of an apparatus for producing a resin sheet according to the present invention, and a die 10 is configured to be able to form a three-layer cylindrical sheet as will be described later. Although three extruders are provided to form a three-layered cylindrical sheet, only two extruders 11 and 12 are shown in FIG. 1, and hoppers 11-1 and 12- of the extruders 11 and 12 are shown. Each resin pellet is inserted into 1, introduced into the die 10 through an internal extrusion mechanism, melted by a heater inside the resin pellet, and discharged from a ring-shaped discharge port described later to form a cylindrical sheet F To do. The pulling-out direction of the cylindrical sheet from the die 10 is vertically downward until reaching the first nip roller described later.

  FIG. 2 shows the structure of a die 10 which is a resin passage portion in an annular die, which corresponds to the molten resin outlet of the tubular sheet extrusion apparatus of the present invention. As is well known, the die 10 is configured to form a desired resin passage structure by appropriately combining various die constituent parts. That is, the die 10 has a ring-shaped discharge port (lip) 14, a tubular molten resin guide path 16 as an extension of the ring-shaped discharge port 14 into the die, and three pipes connected to each guide path 16. Cyclic molten resin introduction passages 18-1, 18-2, 18-3. The inner first molten resin introduction path 18-1 is located in a linear extension of the annular guide path 16 and serves to form an inner layer in the three-layered cylindrical sheet F. The second molten resin introduction path 18-2 is opened downstream of the first molten resin introduction path 18-1 in the molten resin flow direction from the outer peripheral side to the annular guide path 16, and has a three-layered cylindrical sheet F. To form an intermediate layer. The third molten resin introduction path 18-3 opens to the annular guide path 16 from the outer peripheral side downstream of the second molten resin introduction path 18-2 in the flow direction of the molten resin, and has a three-layer cylindrical shape. Helps to form the outer layer in sheet F.

  The die 10 and the block 20 as an upper part thereof are provided with a heater (not shown) for melting the resin pellets from each extruder, and the molten resin is introduced into the molten resin for forming a three-layer cylindrical sheet. Resin supply passages are provided for supply to 18-1, 18-2, and 18-3, respectively. In FIG. 2, only the resin supply passage 22 from the extruder 11 and the resin supply passage 24 from the extruder 12 are shown for simplicity, and resin pellets from the extruder 11 flow into the first molten resin introduction passage 18-1. In the meantime, while being melted, it flows into the annular guide path 16 and forms an inner layer in the cylindrical sheet F. Further, the resin pellets from the extruder 12 are flown into the third molten resin introduction path 18-3, and are flown into the annular guide path 16 while being melted in the meantime, so as to form the outer layer in the cylindrical sheet F. Similarly, it goes without saying that for the formation of the intermediate layer of the cylindrical sheet F, the second molten resin introduction path 18-2 is also provided with a resin supply path from the extruder and the corresponding extruder. Of course, since the adhesiveness of the resin between the multilayers is better as the lamination time in the die is longer, it is necessary to design the length of the melt passage or the like so as to obtain the required adhesiveness.

  In FIG. 2, the die 10 is provided with an air pressure introduction passage 26 for inflation molding, and opens at the lower end on the lower surface of the die 10 inside the ring-shaped discharge port 14. The upper end of the air pressure introduction passage 26 extends to the upper side of the block 20 and is connected to an air pressure source, and the blow pressure is introduced into the air pressure introduction passage 26 as indicated by an arrow a. Is to be done.

  As described below, the present invention seems to flatten the sheet into a gusset bag shape by folding a cylindrical sheet having a circular cross section after inflation molding into an inward V shape on both sides thereof, and wind it on a roll. I have to. In order to perform a smooth transition from the circular cross-sectional shape immediately after inflation to the gusset bag shape, the portion of the cylindrical sheet corresponding to the folded portion of the gusset bag shape can be made slightly thinner during inflation molding. FIG. 3 shows the shape of the lip 14 formed with a protrusion for thinning the folding part. That is, the lip 14 has a ring shape, but three protrusions 14-1 are formed on each of the diametrically opposed inner peripheral surfaces of the lip 14 at each of the diameter opposing portions, and the molten resin from the lip 14 is formed. The portions of the protrusions 14-1 in the tubular sheet formed by discharge become thin by the amount of these protrusions 14-1, and three longitudinal grooves (f1, f1 in FIG. f2, f3). The height of the protrusion 14-1 is set such that the thickness of the tubular sheet after inflation molding is ¼ to ¾ of the total sheet thickness at the portion 14-1.

  In FIG. 1, an air cooling ring 36 is disposed directly below the die 10 concentrically with the inflation sheet take-down path below the die 10. A watering device 38 is disposed on the downstream side. An example of a specific structure of the water cooling device 38 is shown in FIG. 4, cooling water tanks 38-1 provided on both sides of the cylindrical sheet are arranged, and the cooling water from the cooling water tank 38-1 is placed around the entire circumference of the cylindrical sheet. Further, it is swung as shown by an arrow h in FIG. In the present invention, the blown cylindrical sheet is drawn downward, which is preferable from the viewpoint of cooling efficiency because the cooling time can be increased in combination with the method of pouring from above the cooling water.

  A gusset forming device 40 (former) for forming a cylindrical sheet into a gusset shape is disposed downstream of the lower water cooling device 38. The gusset forming apparatus 40 includes a forming cylinder 41, upper and lower nip roller pairs 42 and 42 ', and side plates 43 on both sides of the sheet between the nip roller pairs 42 and 42'. The forming cylinder 41 is for converting the cylindrical shape of the sheet after inflation molding into a gusset shape, and the upper end has a circular section according to the sectional shape of the sheet after inflation molding, and the flatness increases as it goes down. It has a flat shape. 6A shows a perfect circle shape of the upper end portion 41a of the forming cylinder, FIG. 6B shows a slightly collapsed shape of the intermediate portion, and FIG. 6C shows a flat shape of the lower end portion 41b. The forming cylinder 41 includes a forming protrusion 41-1 (a first guide according to the present invention) having a V-shaped cross-sectional shape on the inner peripheral surface thereof. The molding protrusion 41-1 extends in the longitudinal direction of the molding cylinder 41 (vertical direction in FIG. 1), and the height of the molding protrusion 41-1 gradually increases from the upper end 41a to the lower end 41b of the molding cylinder. Exhibits a changing shape. On the other hand, the side wall portion 41 'of the forming cylinder that gradually increases the flatness from the top to the bottom between the forming protrusions 41-1 constitutes the second guide of the present invention. 6A shows that the height of the molding protrusion 41-1 at the upper end 41a of the molding cylinder is zero, FIG. 6B shows the middle height at the middle portion, and FIG. 6C shows the maximum height at the lower end portion 41b. . The surface of the molding cylinder 41 is preferably subjected to a Teflon coating (Teflon is a registered trademark) in consideration of slipping or a fluororesin coating process having good wear resistance and slipping. Processing may be used.

  The tubular sheet F formed by inflation forms three longitudinal grooves f1, f2, and f3 in the longitudinal direction at the respective portions where the diameters oppose each other as described above, but the inside of the tubular sheet is under blow pressure. Yes, the seat is subjected to a relatively slight biasing force outward in the radius (in the expansion direction), and the tip of the molding protrusion 41-1 is engaged with the intermediate groove f1 among the three stripes under expansion pressure. In this way, the grooves f2 and f3 on both sides of the three longitudinal grooves are guided to be folded at the V-shaped leg portions so that they correspond to the folded portions from the V-shaped leg portions to the flat portions on both sides. The position is determined, and it can be easily and reliably folded into the desired gusset shape. That is, the cylindrical sheet F entering the forming cylinder 41 is circular as shown in FIG. 6A, but the positional relationship between the cylindrical sheet F and the forming cylinder 41 is three on both sides of the cylindrical sheet F. Since the leading end of the molding protrusion 41-1 is engaged with the intermediate longitudinal groove f1 among the longitudinal grooves f1, f2, and f3, the folding of the tubular sheet F into the V shape inward is smoothly started. As the cylindrical sheet F advances downward, the side wall 41 'of the molding cylinder 41 is flattened, and the molding projection 41-1 protrudes, so that the guiding action of the molding projection 41-1 and the side wall 41' Flattening and folding progresses as shown in (b), and the vertical grooves f2 and f3 on both sides are thin so that folding back to the upper and lower surfaces is promoted. Finally, as shown in (c), the molding protrusion 41-1 Since the vertical grooves f2 and f3 are located at the connection to the flat surface at the bottom of the base, it is reliably folded back at the longitudinal grooves f2 and f3, and the gusset shape Molding is completed.

  In the present invention, the take-up path of the cylindrical sheet F from the die 10 to the pair of nip rollers 42 and 42 ′ directly below is straight downward, and cooling is performed by cooling water from a water cooling device 38 disposed below the die 10. Therefore, the cooling water flow h is formed along the outer periphery of the cylindrical sheet F and flows into the inner periphery of the forming cylinder 41 of the gusset forming apparatus 40. Therefore, the flow of the cooling water contributes to smoothing the molding surface of the molding cylinder 41 (friction reduction), and smooth gusset molding can be realized.

The cylindrical sheet F folded in the gusset shape is crushed between the upper and lower nip roller pairs 42 and 42 'in FIG. 1, and the side plate 43 penetrates deeply into the V-shaped portions on both sides of the gusset shape between the nip roller pairs 42 and 42'. As a result (see also FIG. 5), the V-shaped portion is deeply folded into a sheet shape.
In FIG. 1, two pairs of nip rollers 42, 42 'are provided, but it is sufficient to provide only the pair of nip rollers 42 immediately after being folded into a gusset shape by the molding apparatus (first after inflation from the die). It is possible to realize a simple gusset fold. The side plate 43 and the downstream nip roller pair 42 'are optional auxiliary means. Further, in FIG. 1, the downstream side of the nip roller pair 44 is shown rotated 90 degrees on the horizontal plane for the convenience of drawing, but it goes without saying that the arrangement is actually orthogonal to the paper surface.

  7 to 9 show a gusset forming apparatus 140 according to another embodiment, and a pair of formed plates provided on the outer periphery of a blown inflation sheet so that the plane thereof is parallel to the diameter at a position opposite to the diameter (this invention). First guide) 141, pressing plates 142 (second guides of the present invention) provided on both sides of the inflation sheet so as to sandwich the flat surface of the forming plate 141, and upper and lower nip roller pairs 143-1 downstream thereof 143-2. The molding plate 141 is provided so as to be movable back and forth in the radial direction (in the direction of the arrow). During the gusset-shaped molding operation, the molding plate 141 is in the advanced position shown in FIG. 7, while the pressing plate 142 is sandwiched between the molding plates 141. Are arranged so as to form a tapered surface (FIG. 8). Therefore, the cylindrical sheet after the inflation molding is opposed to the tapered surface 141a of the molding plate 141 located opposite to the diameter of the cylindrical sheet, and on both sides of the molding plate 141, the inflation sheet is a cylindrical sheet. Guided in a taper. Therefore, the portion of the inflation sheet that contacts the forming plate 141 is gradually folded radially inward, while the portion of the inflation sheet that contacts the pressing plate 142 is pressed flat, and finally, as shown in FIG. As shown, it is molded into a gusset shape. As shown in FIG. 8, the forming plate 141 is smoothly engaged with the V-shaped groove f1 by engaging with the intermediate groove f1 of the three stripes, and the grooves f2, f3 on both sides of the three stripes are smooth. Can be used to smoothly fold both sides of the V-shaped leg.

  In FIG. 1, the sheet F is crushed by the pair of nip rollers 42 and 42 'so that the opposite layers of the sheet are brought into close contact with each other so that the blow air is blocked from the downstream side. In the medical infusion bag to which the present invention is applied, the thickness of the sheet is 150 μm at the thinnest. In the case of such a thick sheet, depending on factors such as the resin constituting the sheet, it is not necessary to simply pass the nip roller. FIG. 10 schematically shows this, and the gusset-folded sheet has four layers at both end portions in the width direction as shown in FIG. The middle part is composed of two layers, and the case where it passes through a nip roller is shown in (b). Since the sheet is thick, the thickness differs greatly between the four layers and the center of the two layers. Then, even if close contact is obtained, it is affected by the large thickness at both ends, so a gap remains in the center, blow air leaks downstream, close contact of the sheet facing surface is not obtained, and the sheet swells Because, the winding of the roll and there is a concern that becomes difficult. According to this inventor's test, the blocking property is dependent on the resin constituting the sheet. Regardless of the difference in blocking properties depending on the material constituting the sheet, a rubber layer is formed on the surface as the nip rollers 42 and 42 'in order to ensure the close contact with the opposite surface of the gusset folded sheet even in a sheet having a thickness of 150 to 350 μm. When the nip between the nip rollers 42 and 42 'is formed, the surface rubber layer is elastically deformed according to the thickness difference between the both end portions and the center portion in the sheet width direction, and as shown in FIG. The sheet facing surface can be brought into close contact with the central portion. As the hardness in the rubber layer, a durometer hardness of A40 to A60 can be adopted. As an alternative, nip rollers 42 and 42 'having a step can be employed. A nip roller 42 having a step on one side or both sides is schematically shown in FIG. 11. In this case, the nip roller 42 has a step on both sides, and the width portion 42-1 of the two-thickness portion of the gusset-folded sheet is the sheet 1 The outer diameter is increased by the thickness of the sheet, and both the four-thickness portion and the two-thickness portion at both ends in the sheet width direction can be mechanically adhered. From the viewpoint of the close contact of the sheet, the temperature of the cooling water from the water cooling device 38 is preferably warmed to 30 ° C. to 60 ° C. from room temperature such as 20 ° C. Since the cooling water is heated, the sheet at the nip roller is softened and the adhesion can be improved. As an index of sheet adhesion, stable roll winding can be realized when the actual sheet peel strength is 0.5 to 30 g / 15 mm, preferably 1.0 to 15 g / 15 mm. Further, the close contact of the sheets is advantageous in that it is possible to eliminate the possibility of air contamination from the cut surface and contamination due to air contamination when a standing bag is cut out from the sheet described later.

  If the gusset shape at both ends of the sheet of the present invention is rolled, there is a concern that it will become an extreme ear height as it is. As a means for eliminating this, a nip roller is provided in front of the take-up roller 52, and by reciprocating the nip roller with a predetermined width, it is possible to take up while properly shifting the positions of both ends, thereby eliminating the ear height. Further, as will be described later, by forming the seal portions on both sides of the sheet, which become the bottom seal when forming the standing bag, through the sheet winding path from the bottom roller 44 to the roll R, both ends in the sheet width direction are sealed, thereby increasing the thickness. To suppress the ear height.

  A bottom roller 44 is positioned below the gusset forming device 40, and the bottom roller 44 is disposed in the water receiving tank 46. The sheet of the gusset-shaped sheet is turned in the transport direction by the bottom roller 44 and pulled out by a pair of side nip rollers 47, and a draining jet air nozzle 48 is arranged on the downstream side of the nip roller 47 so as to be close to each nip roller 47. And excess water is blown away. Thereafter, the sheet is wound around the roll R by the winding roller 52.

  In the present invention, in the inflation molding of the cylindrical sheet, the multilayer sheet from the die is cooled by the air cooling ring 36 as the first stage. For air cooling, cold air of −10 to −20 ° C. may be used by using an ultra-low temperature air generator PUROFRIO manufactured by Hitachi, Ltd. After air cooling, the outer layer is rapidly cooled by cooling water from the cooling device 38, the outer layer is rapidly cooled below the crystallization temperature, the solidification rapidly proceeds, the strain stress is effectively suppressed, the characteristics of the multilayer resin are utilized, and the curl and A multilayer film sheet with less haze and excellent transparency can be obtained. As the water cooling method, cooling is performed by the overflow method described with reference to FIG. 4 or by cooling water from an annular cooling sprinkling ring. The water cooling mechanism includes a cooling water supply pipe that supplies cooling water, a cooling water flow regulator that is provided in the cooling water supply pipe to adjust the cooling water flow rate, and a cooling water supply pipe that is provided in the cooling water supply pipe. And a cooling water heat exchanger for cooling. The temperature is also controlled by circulating the cooling ring. The flow rate of the cooling water flowing down in layers is easily controlled by the cooling water flow regulator, and the temperature of the cooling water is easily controlled by the heat exchanger that receives the flow rate adjustment of the refrigerant. The cooling water is cooled to an appropriate temperature by a heat exchanger, and the flow rate is adjusted by a flow rate adjusting valve. By detecting the amount of cooling water, its temperature, the overflow height of the overflow weir, and feedback control, the cooling efficiency and the cooling performance can be controlled optimally.

  The blow-up ratio (BUR: ratio of the outlet diameter of the annular die and the bubble diameter after completion of the blow-up) in the process of forming the inflation sheet is preferably in the range of 0.7 to 1.2, more preferably 0.8 to 1.4. Although the blow-up ratio of the present invention is kept lower than usual, the internal pressure is lowered by keeping the blow-up ratio low, and in combination with the presence of the longitudinal grooves f1, f2, and f3 on the sheet surface, the gusset shape Folding into becomes easy. Although the thickness of a sheet | seat is not restrict | limited in particular, Preferably it is 120-400 micrometers, More preferably, it is 160-300 micrometers. Furthermore, a resin blending ratio in which the opposing surfaces at the time of bag making are easy to seal in the material configuration is considered.

  The lower limit of the above range of blow-up ratio is determined by the internal pressure during gusset molding. That is, since the gusset molding is performed by engaging the molding protrusion 41-1 of the gusset molding apparatus with the cylindrical sheet from the outside, a pressure that can counter this is required inside the cylindrical sheet. Regarding the upper limit of the blow-up ratio, the adhesiveness (blocking property) of the sheet facing surface after gusset forming is one of the dominant factors. If the internal pressure is too high, the completely contacting state of the facing surface is also caused by the nip by the nip roller 42. There are concerns that cannot be obtained. As will be described later, the blocking property of the sheet made of polyethylene is somewhat inferior to the sheet made of polypropylene even in the same polyolefin type, and in this case the blocking property that requires a lower blow-up ratio is required. It is suitable for securing.

  The amount of air introduced into the multilayer film forming ring die 10 from the air introduction pipe 26 is controlled by opening and closing an air amount adjusting valve (not shown). The amount of air introduced into the multilayer film forming die via the air supply path 26 is controlled by the inflation-up ratio which is the diameter expansion degree of the multilayer film forming die and the synthetic resin sheet formed in the gusset forming apparatus 40. To control. The folding width of the flattened sheet is detected by a folding width sensor installed until winding. Further, the innermost layers are blocked by being pinched by the nip roller 47 and wound up. Sterile air is provided in an air supply pipe that supplies air to a sterile air nozzle and adjusts the air flow rate of air, and an air cooling heat exchanger that is provided in the air supply pipe and cools the air. Formed from.

  As described above, the multilayer film forming ring die 10 has the longitudinal grooves f1, f2, and the like in the multilayer inflation tubular sheet F when the three protrusions 14-1 are provided at the diameter opposite positions on the inner periphery of the lip 14. Since f3 (ruled line) is included, folding can be performed more easily and reliably when folding with a gusset forming apparatus. The depths of the longitudinal grooves f1, f2, and f3 are 50 μm to 180 μm, preferably 70 μm to 130 μm, although depending on the sheet thickness. In terms of the ratio of the sheet thickness at the thin portion to the average thickness of the sheet, 1 / 4 to 3/4.

  The polyethylene sheet of the present invention is a high-density polyethylene (A) and low-density polyethylene (B) extruded at a temperature of the melting point to 200 ° C, preferably 150 ° C to 180 ° C, and a blow-up ratio of 0.7 to 1.2. The hollow sheet formed by co-extrusion through a special circular die is cooled by being brought into contact with air blown from an air-cooled air ring, further cooled with water, crushed by a nip roller, and wound up. By crushing with the nip roller 47, the innermost layers can be blocked (adhered) to prevent entry of bacteria / dust in the subsequent process.

  The molten resin kneaded by heating in the extruder is drawn into a tube shape with a uniform gap between the discharge ports 14 and reduced temperature unevenness in order to make the resin thickness uniform. The sheet thickness is determined by the take-up speed, the screw speed of the extruder, and the BUR (blow-up ratio: ratio of the outlet diameter of the annular die to the bubble diameter after completion of blow-up) in the process of forming the inflation sheet.

And, in case of a polyethylene sheet of the present invention, and each layer density 0.950 g / cm ³ or more high-density polyethylene, density 0.915 g / cm ³ or more high-pressure low-density polyethylene or a density 0.900 g / cm It is preferred to use ³ or more linear low density polyethylene.

[Examples for the production of polyethylene tubular film]
Next, inflation molding was performed using an inflation sheet molding machine shown below.
Molding equipment Three-layer three-layer molding machine manufactured by Plako.
Cylindrical sheet extruder Inner layer extruder: Screw diameter: 40 mmφ: L / D = 28
Intermediate layer extruder: Screw diameter: 65 mmφ: L / D = 30
Outer layer extruder: Screw diameter: 40 mmφ: L / D = 28
Die diameter: 312mmφ
Multiple blowing lip system with air ring.
Temperature: 150-165 ° C
Blow-up ratio (BUR): 0.9.
Die temperature: 165 ° C
Sheet extrusion speed: 3.5 m / min
Molding conditions Molding of HDPE + L-LDPE + / L-LDPE / L-LDPE + HDPE multilayer sheet Outer layer: HDPE: Alloy of L-LDPE = 70: 30 HDPE: Melting point 142 ° C. Density 0.926 MFR = 7 g / 10 min LDPE melting point 124 ℃: MFR 0.9g / 10min Extruder temperature: C1 / C2 / C3 / C4 / AD / J = 160/165/165/165/165/165 ℃
Intermediate layer: L-LDPE
Melting point 124 ° C Density 0.926 MFR = 0.9g / 10min Middle layer extruder temperature: C1 / C2 / C3 / C4 / AD / J = 150/160/165/165/165/165 ° C
Inner layer: LDPE: HDPE = 70: 30 alloy LDPE: melting point 113 ° C .: MFR 2.0 g / 10 min HDPE: melting point 142 ° C., MFR 7 g / 10 min Inner layer extruder temperature: C1 / C2 / C3 / C4 / AD / J = 150/160/165/165/165/165 ℃

  Under the above molding conditions, a multilayer cylindrical sheet of LDPE + HDPE 20 μm / L-LDPE 210 μm / L-LDPE + HDPE 20 μm was obtained.

  In the above examples, the polyethylene structure was described. However, in order to use cyclic polyethylene with little chemical solution adsorption in the inner layer or intermediate layer or to improve the heat resistance of the infusion bag, a modified polyester resin, polypropylene resin, or ethylene propylene is used in the outer layer. A combination of copolymer resins may also be used. In addition, in order to obtain different interlayer strengths, carboxylic acid grafted polyolefin resin is used, and generally known ethylene propylene copolymer (EPR) and ethylene butadiene copolymer ( EBR) and the like can be mixed, and by mixing 5 to 30% / wet, the adhesiveness is advantageously improved. In the method for producing a polyethylene sheet of the present invention, the sheet has an outermost layer containing high-density polyethylene (A) and an intermediate layer made of low-density polyethylene or linear polyethylene (L-LDPE) by an inflation molding method. A hollow tube is formed and the tube is sandwiched between nip rollers, so that the inner surface of the tube on the outer sheet is particularly hygienic with a high-performance filter that prevents dust from entering, making it possible to make standing pouch bags. Thus, a thick polyethylene sheet that is less susceptible to thermal degradation of the resin and that can be added without additives can be produced at low cost and with high productivity.

[Example of Adhesion of Gazette-Folded Sheet (Part 1)]
A test for adhesion (blocking property) was performed on a resin material mainly composed of polypropylene resin. Sumitomo Heavy Industries Modern Co., Ltd., using three 65mmφ extruders for downward inflation molding, 175mmφ round dies with a blow-up ratio of 1.24, line speed of 10m / min each layer olefin made by Mitsubishi Chemical Corporation A resin obtained by blending trade name ZELLUS 7023 resin and ZELLAS MC707 resin, which is a thermoplastic resin, was used. Any resin is constituted by dispersing rubber in a matrix of homopolypropylene. The blend resin of Zelas 7023 and Zelas MC707 is blow-molded at an extrusion temperature of 230 ° C., and cooled using 20 ° C. tap water by the cooling ring device 38 of FIG. 140, both ends of the sheet F were gusset-folded, nipped by a nip roller 143-1 immediately below, and wound on a roll R by a winding device similar to FIG. By niping with the nip roller 143-1, the leakage of blow air was prevented and the proper adhesion and sheet state of the opposing surface were maintained, and stable winding onto the roll R could be performed. In order to evaluate the blocking property, a tensile speed of 50 mm / min is grasped with a Tensilon-type tensile tester for a sheet of 250 μm thick gusset-folded drawn from the roll R that has been wound into an appropriate roll shape. The peel strength between the opposing surfaces was measured at a length of 50 mm. As a result, the peel strength between the sheet facing surfaces of the blocked sheet was 2 to 9 g / 15 mm (0.02 to 0.09 N / 15 mm). That is, the peel strength between the sheet-facing surfaces was within this range for the sheet closely adhered to the facing surface wound in an appropriate roll shape.

[Comparative Examples and Examples (Part 2) of Adhesion of Gazette-Folded Sheets]
A test of adhesion (blocking property) was performed on a resin material mainly composed of polyethylene resin. Novatec LM360, which is a LDPE resin of Nippon Polyethylene Co., Ltd., with a total thickness of 300 μm using 3 down-facing blow molding machines made by Sumitomo Heavy Industries Modern Co., Ltd. Inflation molding of a cylindrical sheet was performed using the layer. The resin temperature at the time of extrusion was 240 ° C., and the blow-up ratio was 1.24. The cylindrical sheet from the extruder was cooled with tap water at 20 ° C., folded on a gusset and nipped with a nip roll, and wound on a roll. Since the nip roll was not sufficiently close to the sheet facing surface, blocking of blow air was insufficient due to the gap between the facing surfaces due to the thickness difference between the four sheets in the gusset state and the other two torso parts. It was difficult to take (Comparative example above).

  When the resin material was subjected to inflation molding of the tubular sheet under the same molding conditions by switching to the above-mentioned Zelas 7023 resin while leaving the outer layer and the intermediate layer as they were, the same adhesion (blocking property) as in Example (No. 1) was obtained. It was possible to wind it on a roll. The peel strength of the raw sheet from the roll was measured with a Tensilon type tensile tester (model used; ORIENTEC / STA-1150) at a tensile speed of 50 mm / min and a grasping length of 50 mm. The peel strength was at least 0.5 g / 15 mm. From the viewpoint of stable roll winding, the peel strength should be higher than this, but if it is too large, the pouch is opened and attached in the spout attachment process after the production of the standing bag by the bag making process described later, or the inner solution is filled. Since it becomes difficult to perform opening by suction, it has been found that the width is preferably within 30 g / 15 mm width, and preferably 15 g / 15 mm width or less.

[Examples of adhesiveness of gusset folded sheet (part 3)]
Again, an adhesion (blocking) test was performed on a resin material mainly composed of a linear polyethylene resin. Nisoron Z 7P07A, a Tosoh Corporation L-LDPE resin, with a total thickness of 250 μm and a surface layer of 40 μm using 3 down-flow extrusion molding machines manufactured by Sumitomo Heavy Industries Modern Co., Ltd. EBR Tuffmer 4085 manufactured by Mitsui Chemicals Co., Ltd. is mixed with the resin at 15% / wt, and the L-LDPE density 0.916 of Tosoh Co., Ltd. prototype resin is used for the intermediate layer 170 μm and the innermost layer 40 μm. Inflation molding of the cylindrical sheet was performed at a speed of 15 m / min. The resin temperature at each extrusion was 230 ° C., and the blow-up ratio was 1.24. The cylindrical sheet from the extruder was cooled with a cooling ring device 21 ° C. tap water, folded on a gusset, and nipped with a nip roll, and wound around a roll. As a result, good blocking was obtained, and a gusset folded sample having a width of 50 mm at both ends could be obtained. The peel strength of the raw sheet from the obtained roll was measured at a tensile speed of 50 mm / min and a grasping length of 50 mm with a Tensilon type tensile tester (model used; ORIENTEC / STA-1150). The blocking of the gusset portion was not the entire surface but was linear with a width of about 15 mm, but the peel strength at that portion was 1.0 to 5 g / 15 mm.

[Manufacture of standing bags from gusset shaped sheets]
In the method for manufacturing a standing bag of the present invention, the upper seal plate and the lower seal plate are inserted while the intermediate seal plates are inserted into the V-shaped recesses on both sides of the gusset-shaped sheet-like tubular sheet drawn from the roll R. By moving each toward the intermediate seal plate, the opposing sheet surfaces of a predetermined width at the upper and lower edges of the folding portion are welded, and then the upper and lower sheets are opposed across the entire width at intervals along the transfer direction. The surface is welded with a predetermined width, and then the side cylindrical sheet is cut in half in the middle that can be placed in the width direction, and the predetermined width portion is cut in the middle along the width direction to form each container As a standing bag. Hereinafter, this method will be described in detail.

  12 and 13, the roll R of the cylindrical sheet is manufactured by the apparatus of FIG. 1, and the gusset portions formed on both sides are indicated by G. The roll R of the cylindrical sheet is mounted on a shaft 54, the roll support shaft 54 is connected to a vector motor (not shown) for rotation of the roll, and a powder brake for controlling the tension of the cylindrical sheet fed from the roll R is provided. I'm damned. Below that, nip rollers 56 and 58 each consisting of upper and lower rollers are installed upstream and downstream in the transport direction of the sheet S of the cylindrical sheet cut out from the roll R. Upper and lower seal plates 64A and 64B for forming a bottom seal of the container provided on both sides of the sheet S sequentially from upstream to downstream along the transfer direction (arrow m) between the nip rollers 56 and 58, respectively. Receiving plates 65 provided between the seal plates and extending in a cantilever manner so as to be inserted from the outside into the sheet gusset shape portion: provided on both sides of the sheet S, and upper and lower cooling for sheet cooling after the bottom seal is formed Bars 66A and 66B: Upper and lower two-stage seal plates 68A and 68B for forming side seals that are twice the width of the container; 70A and 70B: Upper and lower cooling bars 72A and 72B for cooling the seats after forming the side seals Leather blade 74 for splitting in the middle in the width direction: and cutting machine 76 (upper and lower blades 76-1, 76 for cutting into double containers by cutting the double-width side seal portion in the middle From -2 Arranged): is arranged.

  The operation of the molding apparatus from the cylindrical sheet to the individual containers will be described. The cylindrical sheet S pulled out from the roll R on the support shaft 54 is pulled out by the nip rollers 56 and 58. Since the tension of the cylindrical sheet between the nip rollers 56 and 58 is low, the sheet is transferred in the direction of the arrow m between the nip rollers 56 and 58 while being somewhat expanded. Therefore, the V-shaped recesses on both sides of the gusset shape are also transferred with some opening, and as a result, the free end portion of the receiving plate 65 is transferred to the V-shaped recesses on both sides of the sheet gusset shape as shown in FIG. Somewhat introduced. On the other hand, the projecting end portions 64A-1 and 64B-1 for sealing of the upper and lower seal plates 64A and 64B are opposed to the seal receiving plate 65 across the folded edge portion from the V-shaped portion in the gusset shape. The projecting ends 64A-1 and 64B-1 of the seal plates 64A and 64B are opposed to each other in a region having a predetermined width from the upper and lower folded edges from the V-shaped portion in the gusset shape. The upper and lower seal plates 64A and 64B are moved so that the projecting end portions 64A-1 and 64B-1 of the seals abut against the receiving plate 65, and as a result, predetermined upper and lower folded edges from the V-shaped portion in the gusset shape The opposing sheet surfaces are welded together in the width region. FIG. 15 shows a state in which the gusset-shaped sheets are welded to each other at the part y having a predetermined width from the upper and lower folded edges from the V-shaped part. The welding portion y (first welding portion of the present invention) is also shown in FIG. 13 so that the welding of the facing surface at the portion y having a predetermined width from the upper and lower folded edges continues without interruption in the sheet transfer direction m. The welding work by the upper and lower seal plates 64A and 64B and the seal receiving plate 65 is performed. The receiving plate 65 receives only the upper and lower seal plates 64A and 64B, has no sealing function, and does not cause welding portions y having predetermined widths of the inner and outer layers formed on the upper surface side and the lower surface side to be welded.

  The sheet after the formation of the seal portion y is in direct contact with the upper and lower cooling bars 66A and 66B (in FIG. 12, the sheet S is basically connected to the cooling bars 66A and 66B. Receiving cooling due to surface contact), it is subjected to rapid cooling and discharge of residual heat. Although not shown, the cooling bars 66A and 66B circulate cooling water of about 20 ° C. inside and are provided with a chiller for adjusting the temperature of the cooling water. After cooling by the cooling bars 66A and 66B, the sheet S is installed at the center in the sheet width direction, and the sheet S is sealed between the upper and lower opposing surfaces by the upper and lower two-stage seal plates 68A and 68B; 70A and 70B. That is, the seal plates 68A, 68B; 70A, 70B are provided with seal protrusions 68A-1, 68B-1; 70A-1, 70B-1 extending slightly beyond the entire width of the sheet S, and are used for upper and lower seals. The projecting end portions 68A-1 and 68B-1 and the upper and lower sealing projecting end portions 70A-1, 70B-1 are brought into contact with each other so that the width of the projecting projecting end portions 68A-1, 68B-1; 70A-1, 70B-1 is reached. The corresponding upper and lower sheet portions, that is, the opposite portions of the sheet S are welded. This welding part extending in the width direction is represented by z. The welded portion z (second welded portion of the present invention) serves as a side seal of the standing bag as described later, and has a width twice that of the side seal of the standing bag.

  The sheet S after forming the welded portion z is rapidly cooled by direct contact with the upper and lower cooling bars 72A and 72B, and the residual heat is released. Like the cooling bars 66A and 66B, the cooling bars 72A and 72B circulate cooling water at about 20 ° C., and the temperature of the cooling water is adjusted by a chiller. After that, it is cut into two along the central part in the sheet width direction by the leather blade 74 installed in the central part in the sheet width direction, and the cutting line is shown as u (the cutting line u is also shown in FIG. 15). This is the opening of the standing bag. Then, immediately after the nip roller 58, the double-welded welded part z is cut into two standing bags W in the middle by the cutter 76. That is, FIG. 16 schematically shows a state in which the bag is cut into two standing bags W by a cutting machine 76. Each bag W has a predetermined width of the opposite sheet surface at each folded portion from the V cross-sectional shape on both sides of the gusset shaped sheet. The bottom seal W1 is formed by welding (welding portion y) at the center, and the container side surface is cut in the middle between the opposing portions of the cylindrical sheet welded (welded portion z) with a double width at a predetermined interval in the longitudinal direction. Thus, the side seal W2 is formed, and the opening W4 of the standing bag W is configured by cutting the sheet along the middle in the width direction.

  Since the standing bag W obtained in this manner is not directly exposed to the outside air due to the principle of the inflation method, the inside of the cylindrical sheet becomes a completely dust-free environment. Suitable for bags. In the case of a medical infusion bag, after filling the standing bag W with the infusion solution from the opening, a rubber stopper mixed injection port is attached to the opening and sealed. In this case, the infusion bag is convenient in that the mixed injection operation can be performed in a self-standing state.

  As a modified embodiment of the present invention, formation of the welded portion y of the gusset folded sheet serving as the bottom seal W1 of the standing bag W can be performed at the time of inflation molding of the cylindrical sheet described in relation to FIGS. In this case, a heat seal device (seal plates 64A, 64B, etc.) for forming the welded portion y is installed at an appropriate portion of the sheet transfer path on the downstream side of the bottom roller 44 in FIG. When configured in this manner, the thickness at both ends of the sheet is reduced by heat sealing, so that the ear height at both ends when wound on the roll R can be somewhat relaxed without providing the above-described ear height suppressing means. . It is also possible to cut and remove the folded end edge portion of the heat seal portion in order to further suppress the ear height. In addition, it is effective to perform temporary sealing (including blocking) as a method for preventing inversion due to warping of the gusset portion in the subsequent printing or bag making process.

  The standing bag W of the present invention can be used for drugs, electronic substrates and the like in addition to medical infusion applications.

10 ... Die
11, 12 ... Extruder 14 ... Ring-shaped discharge port (lip)
14-1... Projection 20 on the inner periphery of the discharge port 20... Block 26... Air pressure introduction passage 36. Bottom
41-1 ... Molding protrusion 42 ... Nip roller 43 ... Side plate 44 ... Bottom roller 52 ... Winding roller
56, 58… Nip roller
64A, 64B ... Bottom seal plate 65 ... Receiving plate
66A, 66B ... Cooling bar
68A, 68B; 70A, 70B… Seal plate for side
72A, 72B ... Cooling bar 74 ... Leather blade 76 ... Cutting machine 76
F ... Cylindrical sheet
f1, f2, f3 ... longitudinal grooves G formed on both sides of the cylindrical sheet ... gusset-shaped part R ... roll of sheet of cylindrical sheet

Claims (10)

A step of inflation molding cylindrical seat, and while folding the longitudinal side ends of the tubular sheet after inflation molding in gazette shape are brought into close contact with the facing surface is formed into a sheet, wound in a roll process, pulled out from the roll By forming the opposite sheet surfaces at a predetermined width from the upper and lower folding edges of the gusset-shaped portions on both sides of the cylindrical sheet, a first welded portion is formed along the longitudinal direction of the sheet that serves as a bottom seal of each standing bag. A second step along the sheet width direction that serves as a side seal of each standing bag by welding the upper and lower opposing sheet surfaces of the cylindrical sheet at a predetermined width at predetermined intervals in the longitudinal direction of the cylindrical sheet. The process of forming the welded portion, and the vertical facing of the cylindrical sheet along the longitudinal direction at the intermediate portion in the sheet width direction Comprising a step of cutting the over up surface, and forming a cutting portion comprising an opening of each standing bag cut the sheet along the sheet width direction at the intermediate in the second welding portion, standing bags When the medical infusion bag is used and the tubular sheet is subjected to inflation molding, the tubular sheet is drawn downward from the inflation molding die, and the cooling water is formed above the gusset-shaped portion of the tubular sheet drawn out. A method for producing a standing bag, characterized in that the cooling water flows down to the portion of the sheet that is being formed into a gusset shape so as to perform contact chilling and smooth gusset forming by smoothing with cooling water. 2. A method for manufacturing a standing bag according to claim 1 , wherein air blown into the sheet downstream is blocked by bringing the sheet facing surface into close contact when folded into a gusset shape. In the invention according to claim 2 , the method for producing a standing bag is performed such that the sheet facing surface is adhered so that the peel strength is 0.5 to 30 g / 15 mm, preferably 1.0 to 15 g / 15 mm. 3. A method for manufacturing a standing bag according to claim 2 , wherein a uniform adhesion in the full width is maintained by compensating for a difference in thickness in the sheet width direction when folded into a gusset shape. The invention according to any one of claims 1 to 4 , wherein the tubular sheet is formed so that a portion of the tubular sheet that becomes a fold-in part in the gusset shape is thinned when the inflation molding of the tubular sheet is performed. Standing bag manufacturing method. In the invention described in any one of claims 1 to 5, standing bags manufactured wherein the thickness of the sheet is 150～350Myuemu. The step of blow-molding the tubular sheet, the step of forming the sheet into a sheet shape while folding both ends in the longitudinal direction of the tubular sheet after inflation forming into a gusset shape, and winding both sides of the tubular sheet drawn from the roll Forming a first welded portion along the longitudinal direction of the sheet that serves as a bottom seal of each standing bag by welding opposing sheet surfaces at a predetermined width from the upper and lower folding edges of the gusset-shaped portion, and a tubular shape Forming a second welded portion along the sheet width direction that serves as a side seal of each standing bag by welding the upper and lower opposing sheet surfaces of the tubular sheet at a predetermined width at predetermined intervals in the longitudinal direction of the sheet And the upper and lower opposing sheet surfaces of the cylindrical sheet are cut along the longitudinal direction at the intermediate portion in the sheet width direction. That a step, and forming a cutting portion comprising an opening of each standing bag cut the sheet along the sheet width direction at the intermediate in the second weld portion, the standing bags medical infusion bag Blowing into the sheet downstream by bringing the sheet facing surface into close contact with the full width regardless of the level difference between the four layers at both ends in the sheet width direction and the two layers at the center when folded into a gusset shape A method for manufacturing a standing bag, wherein air is shut off. In the invention described in any one of claims 1 to 7, standing bag manufacturing method of a 0.7 to 1.4 blow-up ratio at the time of inflation molding. A standing bag manufactured by the method for manufacturing a standing bag according to any one of claims 1 to 8 , wherein the standing bag for sealed infusion is provided with a rubber stopper mixed injection port attached to a bag body. It is a gusset shaping | molding apparatus used for implementation of the standing bag manufacturing method as described in any one of Claim 1 to 9 , Comprising: In a gusset shape part by engaging with the thin part of a cylindrical sheet | seat from an outer side. A first guide for forming the V-shaped section, and a second guide for forming a flat portion folded from the V-shaped section in the gusset shape by engaging the first guide portion with the surface from the outside. And a gusset forming apparatus.

Images