JP7448794B2 - Packaging bags, bag making and filling methods - Google Patents

Description

The present invention relates to a packaging bag and a bag making and filling method.

Patent Document 1 discloses a packaging bag in which a notch is provided in the lateral seal portion.

JP2020-26304A

In Patent Document 1, it is possible to open the packaging bag and take out the contents without using a knife by tearing the bag main body from the notch.

By the way, there are cases where it is desired that the packaging bag as disclosed in Patent Document 1 be transported while being rolled after being filled with contents.

However, when the present inventors evaluated the ease of rolling the packaging bag of Patent Document 1, they found that there were cases where the packaging bag did not roll well. Additionally, it has been found that if the packaging bag is rolled forcibly, tearing may progress starting from the notch where the load is applied to the packaging bag.

The present invention has been made in view of these circumstances, and it is an object of the present invention to provide a packaging bag that can be easily rolled.

According to the present invention, there is provided a packaging bag, the packaging bag comprising: a cylinder formed by forming a vertical seal part on a film; an upper horizontal seal part; a lower horizontal seal part; and a notch; The upper lateral seal part is provided to close the upper side of the cylinder, the lower lateral seal part is provided to close the lower side of the cylinder, and the notch is provided to close the upper side of the cylinder. A left curved part and a right curved part are provided at both ends of the inner edge of the upper lateral seal part and are convex toward the outside, and the length of the upper lateral seal part in the left-right direction is Ws. A packaging bag is provided in which Wr/Ws and Wl/Ws are 0.1 to 0.4, respectively, where Wl and Wr are the lengths in the left and right direction of the left curved part and the right curved part.

The present inventor conducted extensive research and found that the packaging bag of Patent Document 1 either does not have a curved part at both left and right ends of the horizontal seal part, or the length of the curved part in the left and right direction is too small. It has been found that the packaging bag does not take on a cylindrical shape after being filled with the contents, which makes it difficult to roll. Based on this knowledge, when a curved part was formed so that Wr/Ws and Wl/Ws were each 0.1 to 0.4, the shape after filling with the contents became close to a cylindrical shape. It was found that rolling was made easier by the following methods, and the present invention was completed. It was also found that by making it easier to roll, no unreasonable load is applied to the packaging bag, and tearing starting at the notch becomes difficult to progress.

Various embodiments of the present invention will be illustrated below. The embodiments shown below can be combined with each other.
Preferably, the packaging bag described above is a packaging bag in which, where L is the length of the notch, L/Wl and L/Wr are each from 0.01 to 0.5.
Preferably, in the packaging bag described above, the notch is disposed at a position biased toward the left end or right end of the upper horizontal seal portion, and when the notch is disposed at a position biased toward the left end, the If the distance from the left end of the upper horizontal seal part to the notch is D1, D1/Wl is 1.0 to 2.5, and if the notch is disposed at a position biased toward the right end, the upper side The packaging bag has D2/Wr of 1.0 to 2.5, where D2 is the distance from the right end of the horizontal seal portion to the notch.
Preferably, the packaging bag as described above includes first and second notches as the notch, the first notch being disposed at a position biased toward the left end of the upper horizontal seal portion, and the second notch being located at a position biased toward the left end of the upper horizontal seal portion. It is arranged at a position biased toward the right end of the upper horizontal seal part, and the distance from the left end of the upper horizontal seal part to the first notch is D1, and the distance from the right end of the upper horizontal seal part to the second notch is D2. , D1/Wl and D2/Wr are each from 1.0 to 2.5.
Preferably, in the packaging bag described above, D3/Ws is 0.35 or more, where Ws is the length of the upper horizontal seal portion in the left-right direction and D3 is the distance between the first and second notches. It is a packaging bag.
Preferably, the packaging bag described above is a packaging bag in which the film is a heat-shrinkable film.
Preferably, the bag making and filling method includes a filling step, a lateral sealing step, and a cutting step, wherein the filling step includes placing the contents into a cylinder in which a lower lateral seal portion for closing the lower side is formed. In the lateral sealing step, a lateral sealing portion is formed by performing lateral sealing on the cylindrical body at a position higher than the portion filled with the contents, and in the cutting step, the lateral sealing portion is formed. is cut and divided into upper and lower parts to form an upper horizontal seal part of the packaging bag on the downstream side and a lower horizontal seal part of the cylinder body on the upstream side, and in the cutting process, when dividing the horizontal seal part In this method, a notch is formed at the upper end of the upper lateral seal portion.
Preferably, in the method described above, the film is a heat shrinkable film, and a heat treatment step is provided after the cutting step, and in the heat shrinkage step, the packaging bag separated in the cutting step is heat treated. This is a method of shrinking it.

FIG. 2 is a plan view of the packaging bag 1 without contents. FIG. 2 is a perspective view of the packaging bag 1 with contents inside. FIG. 2 is a layer configuration diagram of film 2. 1 is a configuration diagram of a bag making and filling machine 100. FIG. It is an enlarged view of the vicinity of the horizontal sealing machine 116 of the bag making and filling machine 100, and shows a state in which the horizontal sealing part 11 is formed by the horizontal sealing machine 116. The state after the horizontal sealing machine 116 is opened from the state shown in FIG. After FIG. 6, a state in which the horizontal seal portion 11 is held between the press and cutter 118 is shown. The state after the press/cutter 118 and the ironing roll 115 are opened from the state shown in FIG. 7 is shown. The state after the squeezing roll 115 is closed after the content W is further introduced from the state shown in FIG. 8 is shown. The state after the close contact part 3a has moved to the position of the horizontal sealing machine 116 from the state of FIG. 9 is shown.

Embodiments of the present invention will be described below. Various features shown in the embodiments described below can be combined with each other. Further, the invention is established independently for each characteristic matter.

1. Packaging bag 1
As shown in FIGS. 1 to 3, a packaging bag 1 according to an embodiment of the present invention includes a cylindrical body 3 configured by forming a vertical seal portion 7 on a film 2, an upper horizontal seal portion 4, and a lower side seal portion 7. It includes a horizontal seal portion 5 and a notch 6. Although the packaging bag 1 is normally filled with contents, FIG. 1 shows the packaging bag 1 without any contents for convenience. Examples of the contents include viscous foods such as flower paste, jam, and bean paste.

Hereinafter, the explanation will be made assuming that the top, bottom, left and right of FIG. 1 are the top, bottom, left and right of the packaging bag 1. Specifically, the axial direction of the cylinder 3 is the vertical direction, and the side where the notch 6 is formed is the upper side. The left and right sides of the packaging bag 1 are the left and right sides when the vertical seal part 7 is placed on the front side. Further, the surface on the side of the vertical seal portion 7 is defined as the front surface, and the surface opposite thereto is defined as the back surface.

The length of the packaging bag 1 in the left-right direction is, for example, 140 to 240 mm, preferably 160 to 220 mm. Specifically, this length is, for example, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, and within the range between any two of the numerical values exemplified here. There may be. If this value is too small, the contents may adhere to the inner surface of the packaging bag 1 during bag making and filling, making filling difficult. This problem is noticeable when the contents are highly viscous. The value of [vertical length of packaging bag 1/horizontal length of packaging bag 1] is, for example, 1.5 to 5, preferably 2 to 4. Specifically, this value is, for example, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, and is within the range between any two of the numerical values exemplified here. It may be.

The cylindrical body 3 can be formed by curving the film 2 into a cylindrical shape and heat-sealing the film 2 with both ends overlapped. The vertical seal portion 7 is formed by heat sealing.

The upper side seal part 4 and the lower side seal part 5 are provided so as to close the upper side and the lower side of the cylinder 3, respectively. It is preferable that the horizontal seal portions 4 and 5 are formed along the upper and lower ends of the cylindrical body 3, respectively. It is preferable that the horizontal seal parts 4 and 5 are formed perpendicularly to the vertical seal part 7. The lateral seal portions 4 and 5 can be formed by heat-sealing the cylindrical body 3, respectively.

In one example, the horizontal seal portions 4 and 5 are composed of a plurality of linear seal portions (portions indicated by dotted lines in FIG. 1) 4a and 5a arranged in the vertical direction. Each linear seal part 4a, 5a is provided so as to extend in the left-right direction of the horizontal seal parts 4, 5. It is preferable that the plurality of linear seal parts 4a, 5a are arranged in parallel. The pitch at which the linear seal portions 4a, 5a are provided is preferably 2 to 5 mm. Specifically, this pitch is, for example, 2, 2.5, 3, 3.5, 4, 4.5, 5 mm, and even if it is within the range between any two of the numerical values exemplified here. good.

A notch 6 is formed at the upper end of the upper lateral seal part 4. The notch 6 is a notch or notch, and by tearing the film 2 starting from the notch 6, the packaging bag 1 can be opened and the contents can be taken out. The number of notches 6 may be one or multiple. When the notches 6 are provided at a plurality of locations, the packaging bag 1 can be opened at a plurality of locations, so that the contents can be taken out smoothly.

Film 2 is preferably a heat-shrinkable film. In this case, the packaging bag 1 can be shrunk by subjecting the packaging bag 1 to heat treatment while the packaging bag 1 is filled with the contents. When the packaging bag 1 contracts with the contents filled, the packaging bag 1 becomes approximately cylindrical in the portion of the packaging bag 1 away from the horizontal seal parts 4 and 5, and is transported by rolling (hereinafter referred to as "rolling transport"). ”). On the other hand, in the portions of the packaging bag 1 close to the horizontal seal portions 4 and 5, the packaging bag 1 is difficult to inflate, so the packaging bag 1 has a flat shape, which impedes rolling conveyance of the packaging bag 1. This tendency may be caused by the fact that a curved part that is convex toward the outside is not provided at both ends of the inner edge of the horizontal seal parts 4 and 5, or even if a curved part is provided, its length in the left-right direction is small. This is especially noticeable when

Therefore, in this embodiment, left curved portions 4l, 5l and right curved portions 4r, 5r, which are convex toward the outside, are provided at both ends of the inner edges of the horizontal seal portions 4, 5. Further, when the length of the horizontal seal parts 4 and 5 in the left and right direction is Ws, and the length of the left and right curved parts 4l and 5l and the right curved parts 4r and 5r in the left and right direction are Wl and Wr, Wr/Ws and Wl/ Ws is set to 0.1 to 0.4, respectively. By forming such a curved part, as shown in FIG. 2, the packaging bag 1 can easily swell even in the vicinity of the horizontal seal parts 4 and 5, and its outer shape becomes approximately cylindrical. Transport becomes smoother. Wr and Wl are preferably the same, but may be different from each other. Specifically, Wr/Ws and Wl/Ws are, for example, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, and the numerical values exemplified here It may be within the range between any two. Ws is the same as the length of the packaging bag 1 in the left-right direction. Wl and Wr are, for example, 10 to 100 mm, preferably 20 to 50 mm. Specifically, Wl and Wr are, for example, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 mm, and are within the range between any two of the numerical values exemplified here. Good too.

Further, it is preferable that the left curved portions 4l, 5l and the right curved portions 4r, 5r have an arc shape, and when the radius of curvature thereof is Rl, Rr, Rl/Ws and Rr/Ws are 0.1 to 0, respectively. .4 is preferred. Specifically, Rl/Ws and Rr/Ws are, for example, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, and the numerical values exemplified here It may be within the range between any two. Rl and Rr are, for example, 20 to 60 mm, preferably 30 to 50 mm. Rl and Rr are specifically, for example, 20, 25, 30, 35, 40, 45, 50, 55, 60 mm, and range between any two of the numerical values exemplified here. It may be within.

Further, since the horizontal seal portion 4 is provided with a notch 6, tearing starting from the notch 6 is likely to occur if an excessive load is applied to the vicinity of the horizontal seal portion 4 during rolling conveyance. Therefore, it is particularly important to set Wr/Ws and Wl/Ws to 0.1 to 0.4 for the left curved portion 4l and right curved portion 4r of the horizontal seal portion 4, respectively. On the other hand, the left curved portion 5l and right curved portion 5r of the horizontal seal portion 5 are not essential, and for the left curved portion 5l and right curved portion 5r, even if Wr/Ws and Wl/Ws are less than 0.1. good.

Further, assuming that the length of the notch 6 is L, L/Wl and L/Wr are preferably 0.01 to 0.5, respectively. If this value is too small, it may become difficult to tear the film 2 starting from the notch 6, and if this value is too large, the tearing starting from the notch 6 may progress during rolling conveyance. Specifically, this value is, for example, 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, and may be within the range between any two of the numerical values exemplified here. L is, for example, 3 to 10 mm, preferably 4 to 8 mm. Specifically, L is, for example, 3, 4, 5, 6, 7, 8, 9, or 10 mm, and may be within a range between any two of the numerical values exemplified here.

When the length of the horizontal seal portion 4 in the vertical direction at the portion where the notch 6 is provided is H, L/H is preferably 0.01 to 0.3, more preferably 0.05 to 0.2. . If this value is too small, it may become difficult to tear the film 2 starting from the notch 6, and if this value is too large, the tearing starting from the notch 6 may progress during rolling conveyance. Specifically, this value is, for example, 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, and any two of the numerical values exemplified here. It may be within the range between.

When the horizontal seal portion 4 is composed of a plurality of linear seal portions 4a, the number of linear seal portions 4a having notches 6 is set as N1, and the number of linear seal portions 4a where the extension lines of the notches 6 intersect. (That is, the number of linear seal portions 4a without a notch 6) is N2, preferably N2>N1. N2/N1 is, for example, 1.5 to 10, specifically, for example, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, and the numerical values exemplified here. It may be within the range between any two.

Assuming that the vertical length of the horizontal seal portion 5 on the extension line of the notch 6 is H1, it is preferable that H>H1. Furthermore, if the vertical length of the portion of the horizontal seal portion 4 where the notch 6 is not provided is H2 (=HL), it is preferable that H2>H1. H/H1 and H2/H1 are, for example, 1.1 to 3, specifically, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1. 7, 1.8, 1.9, 2, 2.5, and 3, and may be within the range between any two of the numerical values exemplified here.

The notch 6 is preferably provided at a position where the extension line of the notch 6 does not intersect the curved portions 4l and 4r. This is because if the extension line of the notch 6 intersects the curved portions 4l, 4r, the tear line may be bent at the curved portions 4l, 4r when the film 2 is torn starting from the notch 6.

It is preferable that the packaging bag 1 includes first and second notches 6a and 6b as the notches 6. The first notch 6a is located at a position biased toward the left end of the horizontal seal portion 4, and the second notch 6b is located at a position biased toward the right end of the horizontal seal portion 4. Further, if the distance from the left end of the horizontal seal part 4 to the first notch 6a is D1, and the distance from the right end of the horizontal seal part 4 to the second notch 6b is D2, D1/Wl and D2/Wr are respectively 1. It is preferably 0 to 2.5. If this value is too small, the extension lines of the notches 6a, 6b will intersect the curved portions 4l, 4r. If this value is too large, it may become difficult to take out the contents. Specifically, this value is, for example, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, and may be within the range between any two of the numerical values exemplified here. Note that one of the notches 6a and 6b may be omitted. In this case, D1/Wl or D2/Wr may be within the above range.

When the distance between the first and second notches 6a and 6b is D3, it is preferable that D3/Ws is 0.35 or more. In the packaging bag 1 of this embodiment, the left side of the packaging bag 1 is opened by tearing the front and back films 2 of the packaging bag 1 starting from the first notch 6a, and the left side of the packaging bag 1 is opened starting from the second notch 6b. It is assumed that the contents are taken out by opening the right side of the packaging bag 1 by tearing the front and back films 2. If D3/Ws is too small, the film 2 will be removed starting from the notches 6a and 6b. When the packaging bag 1 is torn, the amount of contents protruding from the packaging bag 1 may become too large, making it difficult to handle. D3/Ws is, for example, 0.35 to 0.6, specifically, for example, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, where It may be within the range between any two of the numerical values exemplified.

As shown in FIG. 3, the film 2 is preferably a laminated film having a base material layer 2a and a sealant layer 2b, and more preferably an adhesive layer 2c is provided between the base material layer 2a and the sealant layer 2b.

The base material layer 2a is arranged so as to be exposed on the outer surface of the packaging bag 1, and the sealant layer 2b is arranged so as to be exposed on the inner surface of the packaging bag 1. By heat sealing the sealant layers 2b, a vertical seal portion 7 and horizontal seal portions 4 and 5 are formed.

The base material layer 2a is made of a material having excellent strength and high impact resistance. As the base material layer 2a, for example, heat-shrinkable polyamide, polyolefin, polyethylene, etc. are used. The adhesive layer 2c is a layer for adhering the base material layer 2a and the sealant layer 2b so as to be laminated with each other, and for example, polyethylene or the like is used as the adhesive layer 2c.

The polyamide of the base layer 2a preferably contains aromatic polyamide. In this case, the base material layer 2a has linear cutability in the MD direction and has excellent barrier properties. There are no particular restrictions on the aromatic polyamide, but resins containing 70 mol% or more of polyamide structural units consisting of xylylene diamine and α, ω aliphatic dicarboxylic acid having 6 to 12 carbon atoms in the molecular chain. etc. can be used. Specifically, homopolymers such as polymethaxylylene adipamide, polymethaxylylene pimeramide, polymethaxylylene azeramide, polyparaxylylene azeramide, polyparaxylylene decanamide, metaxylylene/paraxylylene azylamide, etc. Examples include copolymers such as pamide copolymer, metaxylylene/paraxylylene pimeramide copolymer, metaxylylene/paraxylylene azelamide copolymer, metaxylylene/paraxylylene sepacamide copolymer, etc. Polymethaxylylene adipamide (hereinafter referred to as "MXD6") is preferred because it has excellent basic properties such as strength and gas barrier properties, and is relatively easily available industrially.

The sealant layer 2b can be formed from a resin with excellent heat sealability. The sealant layer 2b can be made of, for example, linear low-density polyethylene. The film constituting the sealant layer 2b is preferably one that can be cut in a straight line in the MD direction.

Moreover, it is preferable that at least one of the base material layer 2a and the sealant layer 2b has straight-line cuttability. In this case, when the film 2 is torn from the notch 6, it is easy to tear it straight. The thickness of the sealant layer 2b is preferably at least twice the thickness of the base layer 2a, and preferably at least half the thickness of the entire film 2.

The film 2 is formed by laminating a base material layer 2a with a thickness of 10 μm to 20 μm, for example 15 μm, an adhesive layer 2c with a thickness of 10 μm to 30 μm, such as 20 μm, and a sealant layer 2b with a thickness of 30 μm to 50 μm, such as 40 μm. The film 2 usually has a thickness of 50 μm to 100 μm.

Further, the base material layer 2a and the sealant layer 2b are bonded to each other by an adhesive layer 2c so as to be laminated with each other. The sealant layer 2b can be adhered to each other. Alternatively, a material other than polyethylene may be used as the adhesive layer 2c, and the base layer 2a and sealant layer 2b may be bonded to each other using a dry lamination method. Alternatively, it is also possible to use fusion bonding without using the adhesive layer 2c. In this way, the film 2 formed from the base layer 2a, the adhesive layer 2c, and the sealant layer 2b has high strength, impact resistance, sealing properties, air-proofing properties, and the like.

2. Bag-making and filling method Next, a bag-making and filling method using the film 2 will be described with reference to FIGS. 4 to 10. This method can be implemented using a vertical bag making and filling machine 100.

<S1: Film bending process>
First, the film 2 unrolled from the roll-shaped original fabric F is guided to the former 112 via a plurality of unrolling rolls 120 and 121. A sensor 119 is placed along the path from the rolled material F to the former 112, which detects registration marks printed on the film 2 at regular intervals in the length direction, and detects registration marks on the path of the bag making and filling machine 100. The film 2 of a certain length can be sent out at certain time intervals. The film 2 is curved into a cylindrical shape while passing through the former 112, so that both side edges of the curved tip overlap. An overlapping portion is formed in the overlapped portion.

Note that a printing process may be provided in which printing is performed on the film 2 at a position before the former 112. It is preferable that this printing be performed on the front surface of the packaging bag 1 (the surface on the side of the vertical seal portion 7). In this case, when the packaging bag 1 that has fallen onto the conveyor 130 in the cutting process to be described later is transported with the vertical seal portion 7 facing upward, it is necessary to check whether the printing is done properly. can.

<S2: Vertical sealing process>
Next, the overlapped portions of the films 2 are heat-sealed using a vertical sealing machine 113 to form a vertically sealed portion 7. The vertical sealing machine 113 is equipped with a pair of sealing rolls, and rotates the pair of sealing rolls in opposite directions while sandwiching the overlapped portion of the film 2 between the pair of sealing rolls in synchronization with the timing when the film 2 moves at regular time intervals. Heat sealing is performed while feeding out the film 2 by rotating it in the direction. By forming the vertical seal portion 7 on the film 2, the cylindrical body 3 is formed.

<S3: Horizontal sealing process>
Next, by rotating the feed roll 114, the cylinder 3 is moved downstream by a predetermined length, and as shown in FIGS. 5 and 6, a predetermined position of the cylinder 3 is heated by a horizontal sealing machine 116. The lateral seal portion 11 is formed by sealing. The horizontal seal part 11 is configured by connecting the upper horizontal seal part 4 of the packaging bag 1 on the downstream side and the lower horizontal seal part 5 of the cylinder body 3 on the upstream side, and is divided into upper and lower parts in the cutting process described later. . The horizontal sealing machine 116 includes a pair of seal bars 116a, and performs heat sealing by sandwiching the above predetermined position between the pair of seal bars 116a for a predetermined period of time.

In one example, the seal bar 116a has a shape in which protrusions and grooves extending in the left-right direction in FIG. 1 are arranged alternately in the vertical direction. In this case, linear seal portions (portions indicated by dotted lines in FIG. 1) 4a, 5a are formed at the portions where the protrusions are pressed.

<S4: Cutting process>
Next, as shown in FIG. 6, by rotating the feed roll 114, the horizontal seal portion 11 is moved to the position of the press/cutter 118. The press/cutter 118 includes a pair of bars 118a.

Next, as shown in FIG. 7, the press/cutter 118 is closed to compress and cool the horizontal seal part 11, and the horizontal seal part 11 is cut with a cutter blade (not shown) to be divided into upper and lower parts. As shown in FIG. 8, an upper horizontal seal portion 4 of the packaging bag 1 on the downstream side and a lower horizontal seal portion 5 of the cylinder body 3 on the upstream side are formed. When the horizontal seal portion 11 is cut, the packaging bag 1 on the downstream side falls onto the conveyor 130. When dividing the horizontal seal portion 11, a notch 6 may be formed in the upper horizontal seal portion 4. By dividing the horizontal seal portion 11 and forming the notch 6 at the same time, it is possible to shorten the manufacturing process.

Further, the notch 6 is formed in the upper horizontal seal part 4 of the packaging bag 1 on the downstream side, and is not formed in the lower horizontal seal part 5 of the cylinder body 3 on the upstream side. Therefore, even if an impact is applied to the lower lateral seal part 5 of the cylindrical body 3 when filling the contents W into the cylindrical body 3, the lower lateral seal part 5 will not be torn. Moreover, since the packaging bag 1 falls with the lower side seal part 5, which does not have a notch, facing downward, tearing of the upper side seal part 4 due to the impact of the fall is suppressed.

The cutter blade has a horizontal blade for dividing the horizontal seal portion 11 into upper and lower parts, and a vertical blade for forming the notch 6. The vertical blade is fixed to the horizontal blade. Vertical blades are more easily damaged than horizontal blades, so they are replaceable. Furthermore, since the longer the vertical blade is, the more likely it is to be damaged, by shortening the notch 6, the frequency of replacing the vertical blade can be reduced.

<S5: Filling process>
Next, as shown in FIG. 8, when the ironing roll 115 is opened, the contents W, which were introduced from the hopper 111 in the previous process and accumulated on the upper side of the ironing roll 115, fall to the lower side of the ironing roll 115. Since the lower horizontal seal portion 5 is formed in the cylinder 3, the dropped contents W are filled into the cylinder 3. A molding device 123 is arranged around the cylinder 3, and the peripheral surface of the cylinder 3 comes into contact with the molding device 123 so that the outer shape of the cylinder 3 is defined.

Next, the contents W are further thrown into the cylinder 3, and when the contents W in the cylinder 3 reach the position of the sensor 122, the contents W are closed by closing the squeezing roll 115 as shown in FIG. W is divided into an upper part and a lower part of the squeezing roll 115. The contents of the lower part of the straining roll 115 are the contents of one bag of the packaging bag 1. Further, by closing the squeezing roll 115, a close contact portion 3a is formed in the cylinder 3, and a bag portion 3b is formed between the close contact portion 3a and the lower horizontal seal portion 5. The packaging bag 1 is formed by forming the upper horizontal seal part 4 on the upper side of the bag part 3b.

<S6: Feeding process>
Next, by rotating the feed roll 114 while keeping the squeezing roll 115 closed, the contact portion 3a is moved to the position of the horizontal sealing machine 116, as shown in FIG. After that, by carrying out the horizontal sealing step in the same manner as S3, the horizontal sealing portion 11 can be formed at a position (close contact portion 3a) higher than the portion filled with the contents W (bag portion 3b).

After this, by repeating the steps S3 to S6, the packaging bag 1 filled with the contents W can be continuously manufactured.

<Heat treatment process>
The packaging bag 1 on the conveyor 130 is transported to a heat treatment furnace and is heat treated in the heat treatment furnace, thereby contracting into a substantially cylindrical shape. Thereafter, the packaging bag 1 is conveyed while being rolled. In this embodiment, since the curved parts 4r, 5r, 4l, and 5l are provided at both ends of the inner edges of the horizontal seal parts 4 and 5, the packaging bag 1 has a nearly cylindrical shape even in the vicinity of the horizontal seal parts 4 and 5. Therefore, the packaging bag 1 can be rolled easily. Moreover, tearing of the film 2 starting from the notch 6 is less likely to occur during rolling conveyance.

Through the above steps, the packaging bag 1 filled with the contents W is manufactured. The packaging bag 1 can be opened by tearing the film 2 on the front and back sides of the packaging bag 1 starting from the notch 6.

3. Other Configurations In the above embodiment, the notch 6 is provided only in the upper horizontal seal portion 4, but the lower horizontal seal portion 5 may also be provided with one or more notches. The position and length of the notch in the lower lateral seal part 5 can be the same as in the upper lateral seal part 4.

1: Packaging bag 2: Film 2a: Base material layer 2b in left and right direction: Sealant layer 2c: Adhesive layer 3: Cylindrical body 3a: Close contact part 3b: Bag part 4: Upper horizontal seal part 4l: Left curved part 4r: Right curve Section 5: Lower horizontal seal section 5l: Left curved section 5r: Right curved section 6: Notch 6a: First notch 6b: Second notch 7: Vertical seal section 11: Horizontal seal section 100: Bag making and filling machine 111: Hopper 112 : Former 113 : Vertical sealing machine 114 : Feed roll 115 : Straightening roll 116 : Horizontal sealing machine 116a : Seal bar 118 : Press and cutter 118a : Bar 119 : Sensor 120 : Feeding roll 121 : Feeding roll 122 : Sensor 123 : Molding Device 130: Conveyor F: Rolled raw material W: Contents

Claims (8)

A packaging bag,
The packaging bag includes a cylindrical body formed by forming a vertical seal part on a film, an upper horizontal seal part, a lower horizontal seal part, and a notch,
The upper side seal part is provided so as to close the upper side of the cylindrical body,
The lower horizontal seal portion is provided to close the lower side of the cylinder,
The notch is provided at the upper end of the upper horizontal seal part,
A left curved portion and a right curved portion that are convex toward the outside are provided at both ends of the inner edge of the upper horizontal seal portion,
When the length of the upper horizontal seal part in the left-right direction is Ws, and the lengths of the left curved part and the right curved part in the left-right direction are Wl and Wr, Wr/Ws and Wl/Ws are 0.1, respectively. ~0.4 ,
A packaging bag , wherein Rl and Rr are radii of curvature of the left curved part and the right curved part, respectively, and Rl and Rr are 35 to 60 mm . The packaging bag according to claim 1,
A packaging bag, where L/Wl and L/Wr are respectively 0.01 to 0.5, where L is the length of the notch. The packaging bag according to claim 1 or claim 2,
The notch is located at a position biased toward the left end or right end of the upper horizontal seal portion,
When the notch is disposed at a position biased toward the left end, and assuming that the distance from the left end of the upper horizontal seal portion to the notch is D1, D1/Wl is 1.0 to 2.5,
When the notch is disposed at a position biased toward the right end, and when the distance from the right end of the upper horizontal seal portion to the notch is D2, D2/Wr is 1.0 to 2.5. bag. The packaging bag according to claim 1 or claim 2,
The notch includes first and second notches,
The first notch is located at a position biased toward the left end of the upper horizontal seal portion,
The second notch is located at a position biased toward the right end of the upper horizontal seal portion,
If the distance from the left end of the upper horizontal seal part to the first notch is D1, and the distance from the right end of the upper horizontal seal part to the second notch is D2, then D1/Wl and D2/Wr are each 1.0 to 1.0. 2.5, packaging bag. The packaging bag according to claim 4,
When the length of the upper horizontal seal part in the left-right direction is Ws, and the distance between the first and second notches is D3,
A packaging bag having a D3/Ws of 0.35 or more. The packaging bag according to any one of claims 1 to 5,
The packaging bag, wherein the film is a heat-shrinkable film. A bag making and filling method comprising a filling process, a horizontal sealing process, and a cutting process,
In the filling step, the contents are filled into a cylinder in which a lower side seal portion that closes the lower side is formed,
The cylindrical body is configured by forming a vertical seal part on a film,
In the horizontal sealing step, a horizontal sealing portion is formed by performing a horizontal seal on the cylinder at a position higher than the region filled with the content,
In the cutting step, the horizontal seal portion is cut and divided into upper and lower parts to form an upper horizontal seal portion of the packaging bag on the downstream side and a lower horizontal seal portion of the upstream cylinder body,
In the cutting step, a notch is formed at the upper end of the upper horizontal seal part when dividing the horizontal seal part ,
A left curved portion and a right curved portion that are convex toward the outside are provided at both ends of the inner edge of the upper horizontal seal portion,
When the length of the upper horizontal seal part in the left-right direction is Ws, and the lengths of the left curved part and the right curved part in the left-right direction are Wl and Wr, Wr/Ws and Wl/Ws are 0.1, respectively. ~0.4,
A method in which Rl and Rr are 35 to 60 mm, respectively, where the radii of curvature of the left curved portion and the right curved portion are Rl and Rr . 8. The method according to claim 7,
The film is a heat shrinkable film,
A heat treatment step is provided after the cutting step,
In the heat treatment step, the packaging bag separated in the cutting step is heat treated to shrink.