JP2005131221A - Film bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film bag with a simple structure which is stable in shape even when it is hung with a liquid filled up in. <P>SOLUTION: A film bag 10 comprises a compartment 30 which is constituted of two pieces of facing film sheets sealed all around. When the bag is hung down, two side seal parts 12 and 13 located in both sides of the compartment which extend in approximately same vertical directions from the bottom are constituted with large width having projecting seal parts 12a and 13a projecting toward the inside of the bag. When the bag is hung, and the liquid is filled up, buckling up curves of both sides of the bag sides are intensive in the projecting seal parts 12a and 13a, resulting in reduced unevenness of transformation of the whole bag. In addition, the more strength of side seal part 12 and 13 is increased, the more projecting deformation can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a film bag configured by sealing the periphery of two opposing films. More specifically, the present invention relates to a film bag having excellent shape stability after filling with a liquid.

  For example, instead of conventional glass containers, synthetic resin containers based on polyethylene, polypropylene, etc. that are lightweight and easy to handle are used as medical containers for storing chemicals used for infusion. It was. Particularly in recent years, film bags with a small waste volume have been favored in the market due to waste disposal problems.

  Of the containers made of polyethylene or polypropylene, the self-supporting rigid container (rigid) has high torso rigidity, so it is always self-supporting in the manufacturing line from container cleaning process to chemical filling, sealing, sterilization, inspection process, etc. There is an advantage that it can be handled. On the other hand, a film bag with a small body rigidity is convenient because it has a small volume when discarded, but cannot be self-supporting on the production line, so a hanging hole at the base of the mouth plug or a hanging hole at the time of infusion It must be manufactured by a suspension line using

  However, since the film bag is highly flexible, when the chemical solution is filled in the hanging line, the lower part of the bag swells in a water droplet shape due to the self-pressure of the chemical solution, and the film bag is significantly deformed. In addition, a phenomenon occurs in which the lower ridge line on both sides of the body part is folded inward, both sides of the bottom seal part are jumped upward, and the center of the bottom seal part is bent.

  If such a drop-shaped deformation of the trunk or a bending deformation around the bottom of the bag occurs, the bulging part on the bag suspension line tends to rub against or catch on the equipment and guides on the line, and scratches or pins This may cause holes. In addition, in the inspection apparatus for foreign matter contamination, there is a problem that an error is caused in the pass / fail judgment due to variations in the body thickness and instability of the bag projection shape due to bending concentrated under the bag. there were.

  As described above, in the conventional film back, its flexibility has been damaged, for example, in the production line by hanging, the bag shape after filling with the chemical solution is not constant, and various problems resulting from this have occurred. .

  In addition, even after manufacturing, once folded film bags are creased, even if the shape is modified, it is easy to bend again at the same position, and the shape of the film bag at the time of final product packaging is not constant. There have been problems such as causing troubles and, in some cases, the bent part of the film bag is rubbed against the package to cause a pinhole.

  As a bag capable of restricting the swelling at the time of storing an infusion, for example, a bag disclosed in Patent Document 1 is known.

Japanese Utility Model Publication No. 54-159793 (FIGS. 1 to 3)

  In the configuration shown in FIG. 1 and FIG. 2 of Patent Document 1, a ribbon is welded to the inner surfaces of two films constituting the bag so that the two films are not excessively separated. In the configuration shown in FIG. 3, the two films are welded not only in the vicinity but also in the inner region, so that the two are not excessively separated.

  Any of the configurations disclosed in Patent Document 1 is effective in restricting the swelling of the bag during infusion storage, but the configuration becomes complicated and the number of manufacturing steps is increased, or the manufacturing cost is thereby increased. The problem remains.

  The present invention was devised to effectively solve the above problems, and provides a film bag having high form stability and a simple structure even when suspended in a state filled with a chemical solution. It is an object.

  The film bag of this invention is equipped with the storage chamber comprised by sealing the circumference | surroundings of two opposing film sheets. And the convex seal part which the two side seal parts of the both sides of the storage chamber extending substantially in the vertical direction when the bag is suspended protrudes toward the inside of the bag at substantially the same vertical height position as measured from the lower end. It is characterized by having a wide structure.

In the film bag of the present invention having the above configuration, since the convex seal portion is provided in the side seal portion, the folding on both sides of the bag when the bag is filled with the liquid is the location of the convex seal portion. Concentrated to occur.
Therefore, variation in deformation for each bag can be eliminated, and as a result, the quality determination accuracy in the foreign matter contamination inspection can be increased.

Moreover, in the location of a convex seal part, since a side seal part is wide, intensity | strength increases. That is, when the liquid is filled, the body of the bag tends to swell in the thickness direction due to water pressure, but the resistance to the bulging increases as the strength of the side seal portion increases, and as a result, Deformation can be kept small.
Therefore, rubbing and catching with equipment and guides on the production line can be prevented, and pinhole generation can be reduced.

  Furthermore, as a result of suppressing variation in deformation during manufacturing, irregular creases do not occur, the shape of the film bag at the time of packing the final product becomes constant, the packing work becomes easy, and the friction with the packing body It is also possible to prevent pinholes due to.

  In addition, although the film bag of this invention is suitable as a medical infusion bag, it is not limited to it, For example, it can also apply to the bag which accommodates a drink etc.

  Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a front view showing an infusion bag 10 according to an embodiment of the present invention.

Configuration of Infusion Bag 10 The infusion bag 10 includes a chemical solution storage chamber 30 configured by sealing the periphery of two opposing film sheets. The infusion bag 10 is suspended in a posture shown in FIG. 1 in a suspension line described later.
In this hanging posture, the chemical solution storage chamber 30 is surrounded by side seal portions 12 and 13 extending in a substantially vertical direction on both sides thereof, and an upper side seal portion 11 and a bottom side seal portion 14 extending in a horizontal direction. Is sealed.
The upper seal portion 11 is provided with a mouth portion 20, and the bottom seal portion 14 is provided with a hanging hole 15 that is used during infusion.
The side seal portions 12 and 13 have convex seal portions 12a and 13a that protrude toward the inside of the bag at the same vertical height position (T). That is, the seal region is wide at the locations of the convex seal portions 12a and 13a. Although described later in detail, the presence of the convex seal portions 12a and 13a can enhance the shape stability of the bag after filling with the chemical solution.

In brief, the production line infusion bag 10 is filled with a chemical solution on the following production line. That is, a large number of infusion bags 10 before being filled with the medicinal solution are moved on a suspension line that holds and hangs the mouth portion 20 and is sequentially filled with the medicinal solution from the mouth portion 20. Next, after the mouth portion 20 is sealed with a rubber stopper or the like, each bag is moved to the foreign matter mixing inspection line while being in the same suspended state.
When the infusion bag 10 is used for an actual drip, the infusion bag 10 is turned upside down from the state of FIG. The drip tube is connected to the mouth 20 facing downward.

Improved shape stability due to the presence of the convex seal portions 12a, 13a In the infusion bag 10, the side seal portions 12, 13 are provided with the convex seal portions 12a, 13a, thereby improving the shape stability of the bag after filling with the chemical solution. ing. This will be described below in comparison with a conventional infusion bag that does not have the convex seal portions 12a and 13a.
2 (a) shows the conventional infusion bag 50 without the convex seal portions 12a and 13a, and FIG. 2 (b) shows the infusion bag 10 of the present invention with the convex seal portions 12a and 13a, respectively. It is shown in a state after 20 is grasped and suspended and filled with a chemical solution. In general, since a film bag is highly flexible, the lower side of the bag swells in the form of water droplets and the side of the bag bends inward after the chemical solution is filled. This is the same in the infusion bag 10 of the present invention and the conventional infusion bag 50.

However, in the conventional infusion bag 50 which does not have the convex seal portions 12a and 13a, (1) the bent portions on the side seal portions 12 and 13 are not constant for each bag, (2) the side seal portion 12 and Since the strength of 13 is low, there is a problem that bending is large, and the bottom seal portion 14 is also bent, resulting in a large bulge amount.
As a result of these, on the suspension line of the infusion bag 50, the bulging portion is liable to be rubbed and caught with the equipment and guides on the line, which may cause scratches and pinholes. Furthermore, in the foreign matter contamination inspection, the quality of the pass / fail judgment is caused by an error due to variations in the thickness of the body portion and instability of the bag projection shape due to bending concentrated below the bag.

  In addition, once the film bag is bent, it will be bent once, so even if the shape is modified, it will easily be bent again at the same position, and the shape of the film bag at the time of packing the final product will not be constant. This may cause troubles or, in some cases, the bent part of the film bag may rub against the package to cause pinholes.

On the other hand, in the infusion bag 10 of the present invention, the side seal portions 12 and 13 are provided with the convex seal portions 12a and 13a (see FIG. 1), so that the folding on the side seal portions 12 and 13 is performed. The bending always occurs at the locations of the convex seal portions 12a and 13a. Thereby, the above problem (1) is solved.
Moreover, since the sealing region is wide at the convex seal portions 12a and 13a, the strength of the side seal portions 12 and 13 is increased, and the degree of bending with respect to the self-weight water pressure of the chemical solution is reduced. The bulge amount of the bag is also reduced. Thereby, the above problem (2) is solved.

For film bags A, B, and C having three types of dimensions and shapes, various changes are made to the protruding heights (H) and vertical height positions (T) of the convex seal portions 12a and 13a. 500 ml was filled, and the degree of bulging and bottom breaking were compared in that case.
In the present invention, the vertical height position (T) is a height measured from the lower ends of the side seal portions 12 and 13, and the lower ends in this case are the left and right lower corners of the chemical solution storage chamber 30 ( This means the point C1 or C2) in FIG. This is the same even in the case of the chemical solution storage chamber 30 based on the hexagon shown in FIGS. Moreover, the height position (T) of both convex seal parts 12a and 13a is substantially the same.

The bags A and C have the dimensional shape shown in FIG. That is, the chemical liquid storage chamber 30 has a total width of 138 mm, a side height of 185 mm, and a mouth height of 195 mm, which is a pentagonal shape.
The bag A is made of a polyethylene multilayer film having a thickness of 250 μm, and the bag C is made of a polypropylene multilayer film having a thickness of 210 μm.

The bag B has the dimensional shape shown in FIG. That is, the chemical liquid storage chamber 30 has a total width of 138 mm, a side height of 185 mm, a mouth height of 205 mm, and a hexagonal shape. Unlike the bags A and C, the bag B has a bottom seal portion 14 formed in a V shape and has a recessed valley shape. The depth of this valley is 5 mm.
The bag B is made of a polyethylene multilayer film having a thickness of 250 μm.

  The seal widths of the peripheral seal portions of the bags A, B, and C are the same, and the side seal portions 12 and 13 are formed to have a width of 5 mm on both sides and the bottom seal portion has a width of 5 mm. The seal part on the upper side has a width of 8 to 20 mm, and the width increases as it approaches the mouth.

Table 1 shows the results of comparative experiments.

  In Table 1, “swelling of water droplets” indicates the degree of increase in bag thickness due to filling with water for injection (the degree of swelling), and the degree of swelling is small as x, Δ, ○, ◎. I mean. Further, “bottom fold” indicates how the bottom seal portion 14 is folded due to filling with water for injection, and means that the fold is less as x, Δ, ◯, and ◎.

Table 1 shows the following.
(1) As for the protruding height H (mm) of the convex seal portions 12a and 13a, even if 1 mm is effective, a stable effect is obtained by setting it to 3 mm or more, and it is particularly preferably 5 to 10 mm.
However, even if the height is set to 13 mm or more, there is no significant difference in the effect.
Therefore, the following can be said. Assuming that the total width of the chemical solution storage chamber 30 is a, a = 138 (mm). Therefore, the dimension range of the protruding height (H) is about (a / 100) ≦ H ≦ (a / 10), that is, It is preferable that 1.38 ≦ H ≦ 13.8.
(2) When the vertical height position T (mm) of the convex seal portions 12a and 13a is set to 14 mm (corresponding to about 10% of the width dimension of the chemical solution storage chamber 30), it is effective in preventing the bottom side from being bent, In terms of prevention, the effect is not sufficient. It is considered that this is because the convex seal portions 12 a and 13 a are too close to the lower edge of the chemical solution storage chamber 30.
When the height position T is set to 74 mm (corresponding to about 53% of the width dimension of the chemical solution storage chamber 30), although some bottom folds are recognized, the effect is sufficient for preventing bulging, and the whole is generally good. .

Regarding the vertical height position T of the convex seal portions 12a and 13a, generally, a range that satisfies both the prevention of bulging and the prevention of bending of the bottom can be obtained from the following equation (1).

The process of deriving equation (1) will be described with reference to FIG. FIG. 4 is a drawing schematically showing only the chemical solution storage chamber 30 of the bag.
In FIG. 4, circles A1 and A2 are circles drawn around the lower corners C1 and C2 of the storage chamber 30, respectively, and the radii are both a / 2 (a is the full width of the storage chamber).
Therefore, if the radius of the circle A1 is R1,

よって、図４中、Ｔ１およびＴ２は、次式（４）および（５）で表される。

On the other hand, the circle B is a circle circumscribing both the circles A1 and A2. If the radius of the circle B is R2, geometrically from FIG.

Therefore, in FIG. 4, T1 and T2 are expressed by the following equations (4) and (5).

  The vertical height position (T) is preferably in the range of (T1) / 2 ≦ T ≦ T2. That is, it is considered that the height T is preferably in the range of the above formula (1). The reason for thinking so is as follows.

That is, when there is no convex seal part 12a, 13a, when a chemical solution is put into the chemical solution storage chamber 30, a region near the lower corners of the storage chamber 30 (one of the regions is indicated by a hatched region in FIG. 4). , And try to swell in a conical shape with the points C1 and C2 as apexes. It is considered that the side seal portions 12 and 13 are most easily bent at positions on the side seal portions 12 and 13 corresponding to the bottoms of the cones (point M in FIG. 4). That is, it is considered that providing the convex seal portions 12a and 13a at this position is effective for suppressing the bending.
Therefore, with the distance (= R1) between the point C2 and the point M as a reference, a range in which the width of the radius of the circle B (= R2) is provided above and below, and further, as a result of repeating the experiment, Regarding the length of T1), the range multiplied by a factor of 1/2, that is, the range represented by the above equation (1) is considered preferable as the height position (T) for providing the convex seal portions 12a and 13a. It was.

  From the above equation (1), the chemical bag 10 having the total width a = 138 mm of the chemical solution storage chamber 30 is approximately 20 (mm) ≦ T ≦ 98 (mm), and the measurement results (T = 14 is insufficient, and T = 74 was generally good.)

つまり、凸シール部１２ａ、１３ａを設ける高さ位置（Ｔ）は、谷の深さβだけ下方にスライドすることとなる。
このような補正をする理由は、次の通りである。すなわち、底辺シール部１４が谷状となっていることに起因して、液体は薬液収容室３０のより深い位置にまで到達する。それに対応させて、側方シール部１２、１３上で応力を集中させるべき位置（すなわち、凸シール部１２ａ、１３ａを設ける位置）も下方へとスライドさせた方が良いと考えたからである。 Correction value β when bottom seal 14 is mountain-shaped or valley-shaped
Next, an equation for correcting the above equation (1) when the bottom seal portion 14 has a mountain shape or a valley shape will be described.
FIG. 5 shows a case where the bottom seal part 14 has a valley shape. For the sake of clarity, the valley is partially enlarged and the valley depth is exaggerated. β indicates the depth of the valley. In such a case, β is subtracted from the lower limit value T1 and the upper limit value T2 in the range of T shown in the above equation (1). That is,

That is, the height position (T) at which the convex seal portions 12a and 13a are provided slides downward by the valley depth β.
The reason for such correction is as follows. That is, the liquid reaches the deeper position of the chemical solution storage chamber 30 due to the bottom seal portion 14 having a valley shape. This is because it is considered that the position where stress should be concentrated on the side seal portions 12 and 13 (that is, the position where the convex seal portions 12a and 13a are provided) should be slid downward correspondingly.

つまり、凸シール部１２ａ、１３ａを設ける高さ位置（Ｔ）は、山の高さβだけ上方にスライドすることとなる。
このような補正をする理由は、次の通りである。すなわち、底辺シール部１４が山状となっている場合、山が高くなる程、側方シール部１２、１３がバッグ内方へと向かって折れ曲がろうとする度合いが低くなる。それに対応させて、側方シール部１２、１３上で応力を集中させるべき位置（すなわち、凸シール部１２ａ、１３ａを設ける位置）も上方へとスライドさせた方が良いと考えたからである。 FIG. 6 shows a case where the bottom seal part 14 has a mountain shape. For the sake of clarity, the mountain is partially enlarged and the height of the mountain is exaggerated. β indicates the height of the mountain. In such a case, β is added to the lower limit value T1 and the upper limit value T2 in the range of T shown in the above formula (1). That is,

That is, the height position (T) where the convex seal portions 12a and 13a are provided slides upward by the height β of the mountain.
The reason for such correction is as follows. That is, when the bottom seal part 14 has a mountain shape, the higher the mountain, the lower the degree that the side seal parts 12, 13 tend to bend toward the inside of the bag. This is because the position where stress should be concentrated on the side seal portions 12 and 13 (that is, the position where the convex seal portions 12a and 13a are provided) should be slid upward correspondingly.

  In the above, the example which applied this invention to the medical infusion bag was demonstrated as one embodiment. However, what has been described above also applies to film bags that contain beverages and the like. Thus, the present invention is not limited to medical infusion bags, and can be applied to all film bags filled with contents in a suspended state at least on a production line.

The front view which shows the infusion bag which concerns on one Embodiment of this invention. Explanatory drawing which compares and demonstrates the infusion bag of FIG. 1 and the conventional infusion bag. The figure explaining the dimension of the infusion bag used in the Example. The schematic diagram explaining the derivation | leading-out process of the formula showing the position which forms a convex seal | sticker part. Explanatory drawing explaining the correction value (beta) of the formula showing the position which forms a convex seal | sticker part. Explanatory drawing explaining the correction value (beta) of the formula showing the position which forms a convex seal | sticker part.

Explanation of symbols

10 Infusion bag (present invention)
DESCRIPTION OF SYMBOLS 11 Upper side seal part 12, 13 Side seal part 12a, 13a Convex seal part 14 Bottom side seal part 15 Hanging hole 20 Mouth part 30 Chemical solution storage chamber 50 Infusion solution bag (conventional example)

Claims (5)

A film bag having a storage chamber configured by sealing the periphery of two opposing film sheets,
Convex seals in which two side seal portions on both sides of the storage chamber extending substantially vertically when the bag is suspended project toward the inside of the bag at substantially the same vertical height position (T) as measured from the lower end thereof. A film bag characterized by having a wide portion and having a portion. The film bag according to claim 1, wherein the vertical height position (T) is within a range defined by the following equation, where a is the full width dimension of the storage chamber.

The bottom seal portion located below the storage chamber when the bag is suspended is configured in a mountain shape that rises above the horizontal line connecting the lower ends of the two side seal portions,
2. The vertical height position (T) is within a range defined by the following expression, where a is the full width dimension of the storage chamber, and β is the height of the peak of the mountain. Film bag.

The bottom seal portion located below the storage chamber when the bag is suspended is configured in a valley shape that is recessed below the horizontal line connecting the lower ends of the two side seal portions,
2. The film according to claim 1, wherein the vertical height position (T) is within a range defined by the following equation, where a is the full width dimension of the storage chamber, and β is the depth of the valley. bag.

The total width dimension of the storage chamber is a, and the protruding height (H) of the convex seal portion is within a range defined by the following formula. The film bag described.

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