EP3891080B1 - Bag and film tube for producing such a bag - Google Patents

Description

The invention relates to a sack with a filling space for bulk material, which is delimited by a lower base, a peripheral wall and an upper filling space closure facing away from the lower base. The sack has a tear strip for releasing an opening field of the sack, which is delimited by an upper weakening line and a lower weakening line, both weakening lines running parallel to the upper filling space closure and the upper weakening line being positioned between the upper filling space closure and the lower weakening line.

Such a bag is, for example, from the EP 0 620 157 B1 known. With the help of the tear strip, the entire area of the bag above the strip is separated from the lower part of the bag containing the contents. The weakening lines and also a front line that runs perpendicular to the two weakening lines and where the tear strip begins are each perforated. To open the tear strip, the front line perforation is pressed in with a finger of the person opening the bag and then the tear strip in this area is grasped from the inside of the bag material and from the outside of the bag material with the thumb and index finger and further torn open along the weakening lines. However, handling the opening is not clean, as the operator comes into contact with the contents of the bag when tearing it open and also the perforation along the forehead line is not always carried out correctly.

More bags are from DE 38 36 227 A1 , FR 2 951 439 A1 , EP 0 779 222 A1 , EN 20 2016 102623 U1 , EP 2 059 456 A1 , WO91/06488 A1 , WO 2016/100852 A1 and WO 00/43272 A1 known.

The invention is based on the object of providing a bag of the type mentioned at the beginning with improved opening options.

The invention is achieved by a sack according to claim 1, in which the sack has a longitudinal seam running transversely to the upper filling space closure, the upper and lower weakening lines beginning in the region of the longitudinal seam and the longitudinal seam being weaker in the region between the two weakening lines than above the upper weakening line and below the lower weakening line. The tear strip therefore adheres less strongly to the sack material located in the region of the longitudinal seam below the tear strip and can easily be fixed between the thumb and index finger of an operator, first removed from the sack material located below the tear strip in the region of the longitudinal seam and then torn open along the weakening lines. The operator's fingers do not touch the contents in the sack.

The bag advantageously has a disruptive substance in the area of the longitudinal seam between the two weakening lines that hinders the welding process. This is particularly preferably formed by a varnish that is applied in the area of the longitudinal seam between the weakening lines in the manner of a grid either on the side of the tear strip facing the filling area or on the side facing the filling area. opposite side of the bag material below the tear strip. The varnish is preferably selected so that the adhesion of an additional melt to form the longitudinal seam on the varnish is significantly weaker than on the remaining bag material in the area of the longitudinal seam.

In a particularly preferred embodiment of the invention, a flag is arranged at the beginning of the tear strip between the two weakening lines, which extends beyond the longitudinal seam in the opposite direction to the tearing direction and does not adhere to the material of the wall of the bag. With the help of the flag, an operator can particularly easily grip the beginning of the tear strip and open the tear strip in the tearing direction along the weakening lines. If the bag is formed from a film web that is folded over to form a film tube, with the two sides of the film web being placed on top of one another and connected with the longitudinal seam, the flag is particularly preferably formed by pulling the upper film slightly beyond the longitudinal seam over the lower film web in the circumferential direction. This creates a film strip along the longitudinal seam that is not connected to the film underneath. The two weakening lines then also extend beyond the longitudinal seam to the lateral end of the upper film of the bag. However, the weakening lines do not extend to the lower film in the area of the longitudinal seam. The positioning indication of the beginning of the weakening lines in the area of the longitudinal seam is to be understood in the sense of this invention in such a way that the weakening lines either begin where the longitudinal seam runs or, when the aforementioned flag is formed, extend slightly beyond the longitudinal seam against the tearing direction.

In a preferred embodiment of the invention, the bag material in the area of the ends of the weakening lines and the material and the width of the tear strip are designed in such a way that the resistance to tearing the tear strip beyond the ends of the weakening lines is greater than the resistance to tearing the tear strip off the bag. When the opening field is opened along the weakening lines, the bag can therefore only be opened up to the end of the weakening lines and not beyond, since if the tear strip is pulled further, the bag does not open any further, but the tear strip tears off. The ends of the weakening lines are understood to mean the side of the weakening lines towards which the tear strip is opened during tearing along the weakening lines, exposing the opening field.

In a particularly preferred embodiment of the invention, the bag consists of a film which can be constructed in one or more layers.

According to the invention, the bag is a side-gusseted bag with a front side and a back side, which are connected to one another via a first side wall and a second side wall, wherein the side walls are each formed by side gussets. The weakening lines extend across at least 80% of the width of the front side or the width of the back side of the bag, in particular across the entire width of the front side or across the entire width of the back side. However, the area of the side gussets remains free of the weakening lines. This design allows the desired V-shaped chute to be formed below the opening field in a side-gusseted bag, which is particularly advantageous due to the positioning of the lower weakening line.

Both the pouring out of the bulk material in the bag and its dosing are possible with the EP 0 620 157 B1 disclosed bag is difficult because the person emptying the bag has to grasp it with the hand of their first arm below the bottom of the bag and place the upper part of the remaining bag over the forearm of the second arm and then tilt the bag using the hand of the first arm. In order to make emptying easier, the upper filling chamber closure therefore has, in a particularly preferred embodiment of the invention, a fingertip contact area on its inside facing the filling chamber. The fingertip contact area is formed by a material fold between a first leg and a second leg of the bag, the first leg extending from the upper weakening line to the material fold and the second leg adjoining it starting from the material fold. The material fold can either be formed in a one-piece film by a fold or the introduction of a seam or by two films being connected to one another with a sealing seam. The first leg and the second leg of the bag are each formed by the bag material surrounding the filling chamber. The bag is dimensioned and the tear strip positioned in such a way that the two legs of a bag filled with product, with the opening panel open, can be pulled open when the bag is carried by engaging in the opening field encloses an angle of no more than 135°. The bag is carried by the hand of an operator, for example, i.e. an operator reaches into the opening field with one hand and the first leg rests on the operator's hand, while the bag, carried by the hand, hangs down from it. The dimensions of the bag are thus selected in such a way that an angle of no more than 135° is formed in the aforementioned state of the bag. It has been shown that this design makes it possible to carry the bag safely by reaching into the open opening field.

According to the invention, the distance between the upper weakening line and the material bevel is 30 to 65 mm, particularly preferably 45 to 55 mm, and the distance between the lower weakening line and the upper weakening line is 15 to 25 mm. The peripheral wall of the bag has a front and a back, with both weakening lines being centered either on the front or on the back of the bag and extending over 15 to 35% of the bag circumference.

The bag is opened along the weakening lines, whereby the position of the weakening lines determines the position of the opening field in the bag. When opened, the opening field has the shape of a rectangle with a height corresponding to the distance between the weakening lines and a length corresponding to the length of the two weakening lines. The opening field is centered either on the front or on the back of the bag and extends over 15 to 35% of the bag's circumference.

It has been found that when the opening field is positioned in this way via the aforementioned positioning of the two weakening lines, the bag material between the upper material edge and the upper weakening line and thus the upper edge of the opening field can be used together with the material of the upper material edge for the hand of the other arm of the person emptying the bag. The resulting handle is voluminous and at the same time firm enough to allow the bag to be easily emptied. If the upper weakening line and thus the upper edge of the opening field are moved further towards the bottom of the bag, the fingers of the person to be operated no longer additionally grip the upper material edge, which means that the handle loses a lot of stability and the person emptying the bag loses control over the bag. If, on the other hand, the opening field is moved further towards the upper material edge by shortening the distance between the upper weakening line and the material edge beyond the inventive extent, the handle becomes very narrow and uncomfortable. Especially if the bag is heavier, an operator would have to carry the weight primarily with the fingertips and no longer with the entire hand.

By centering the opening field on the front or on the back of the bag, the weight of the bag can be more easily balanced when emptying. By keeping the two weakening lines at a distance of 15 to 25 mm from each other and thus by the targeted height of the opening field in conjunction with the extension of the weakening lines and thus also of the opening field Over 15 to 35% of the circumference of the bag, a V-shaped chute is created along the lower edge of the opening field, resulting from the lower weakening line, which enables targeted dosing and pouring direction.

A person emptying the sack grasps the sack with the hand of the first arm below the bottom of the sack. With the hand of the second arm, the person reaches into the opening area and takes the sack material between the upper edge of the opening area and the material edge, as well as the material edge itself, in the form of a stable handle. As soon as the person holds the sack at an angle by lifting the bottom or lowering the opening area, the lower edge of the opening area forms a V-shaped chute that extends outwards, through which the bulk material can be dispensed very easily and in a well-dosed manner.

In a particularly preferred embodiment of the invention, the upper former filling space closure is formed by a transverse seam, whereby the transverse seam also forms the material fold inside the bag. This embodiment is particularly present when the bag is a side-gusseted bag.

In an alternative embodiment, the upper filling chamber closure is formed by an upper base and the material fold is formed by the transition of the surrounding wall of the bag to the upper base. The material fold can either be a fold made in a film or the material The bag is additionally sealed in this area. This design is particularly present when the bag is a valve bag.

The invention is also achieved by a film tube according to claim 8 for producing bags of the aforementioned type. The film tube has a plurality of tear strips arranged parallel to one another at equal distances to release an opening field. The tear strips are each delimited by an upper weakening line and a lower weakening line. The film tube is formed from a film web that is folded over to form a tube, the film tube having a longitudinal seam running along the film tube that connects the two superimposed lateral ends of the film web to one another, thereby forming the film tube. The wall of the aforementioned bags is of course also designed accordingly. This design of the film tube allows a bag of the aforementioned type according to the invention to be produced from the film tube, with the advantages mentioned in connection with the bags according to the invention.

In a particularly preferred embodiment of the invention, at the beginning of each tear strip of the film tube, between the two weakening lines associated with this tear strip, a flag is arranged, which extends beyond the longitudinal seam in the opposite direction to the tearing direction and does not adhere to the material of the wall of the film tube. The resulting bags according to the invention for the film tube according to the invention thus have the The advantages described above in connection with the bags when opening the opening field are shown in the flags.

According to the invention, the film tube has a plurality of material bending areas arranged at constant intervals transversely to the longitudinal extension of the film tube for introducing a material bend each, which is each assigned to a tear strip. The distance between the upper weakening line and the assigned material bending area is 30 to 65 mm, in particular 45 to 55 mm, and the distance between the lower weakening line and the upper weakening line of each tear strip is 15 to 25 mm. The weakening lines are arranged centrally on the film tube in its flat state and extend over 15 to 35% of the film tube circumference. This design of the film tube allows a sack of the aforementioned type to be made from the film tube with the advantages already listed for this sack above.

In a preferred embodiment of the film tube according to the invention, the films of the film tube in the area of the ends of the weakening lines and the material and the width of the tear strip are designed in such a way that the resistance to tearing of the tear strip beyond the ends of the weakening lines is greater than the resistance to tearing of the tear strip from the film tube. Here too, with a film tube designed in this way, A sack of the aforementioned type can be produced from the film tube according to the invention with the advantages mentioned for this sack.

Fig. 1

ein erfindungsgemäßer Sack mit geschlossenem Öffnungsfeld,

Fig. 2

ein erfindungsgemäßer Sack entsprechend Fig. 1 mit entlang der Schwächungslinien aufgerissenem Aufreißstreifen,

Fig. 3

den Gegenstand aus Fig. 2 in Schüttposition, den Griff und die V-förmige Schütte zeigend und

Fig. 4

einen Ausschnitt eines flachgelegten Folienschlauches.

Further details and advantageous embodiments of the invention are explained below using a schematically illustrated bag and a schematically illustrated section of a film tube according to the invention; they show:

Fig.1

a bag according to the invention with a closed opening field,

Fig. 2

a bag according to the invention according to Fig.1 with tear strip torn along the weakening lines,

Fig.3

the object from Fig. 2 in pouring position, showing the handle and the V-shaped chute and

Fig.4

a section of a flattened film tube.

In the following, elements of the invention that have the same effect are given a uniform reference number where this makes sense. In particular, elements of the bag according to the invention that are also found in the film tube according to the invention are given a uniform reference number. The features of the invention explained below using the exemplary embodiments can also be the subject of the invention individually or in combinations other than those shown in the exemplary embodiment.

Fig. 1 to 3 show a bag 2 according to the invention with a filling space for bulk material, which is delimited by a lower base 4, a circumferential wall 6 and an upper filling space closure 8 facing away from the lower base 4. The bag 2 has a tear strip 10 for releasing an opening field 12 of the bag 2, which is delimited by an upper weakening line 14 and a lower weakening line 16. Both weakening lines 14, 16 run parallel to the upper filling space closure 8 and the upper weakening line 14 is positioned between the upper filling space closure 8 and the lower weakening line 16. The bag 2 has a longitudinal seam 18 running transversely to the upper filling space closure 8. The upper and lower weakening lines 14, 16 each begin in the area of the longitudinal seam 18. The longitudinal seam 18 is weaker in the area between the two weakening lines 14, 16 than above the upper weakening line 14 and below the lower weakening line 16.

At the beginning 20 of the tear strip 10 between the two weakening lines 14, 16, a flag 22 is arranged which extends beyond the longitudinal seam 18 in the opposite direction to the tearing direction, the tearing direction being indicated by the arrow 24 in the exemplary embodiment, and does not adhere to the material 26 of the wall 6 of the sack 2 in this area.

The bag material in the area of the ends 28 of the weakening line 14, 16 and the material and the width of the tear strip 10 are designed in such a way that the resistance to tearing of the tear strip 10 over the ends 28 of the Weakening lines 14, 16 is greater than the resistance against tearing of the tear strip 10 from the bag 2.

In the embodiment shown, the bag 2 is a side-gusseted bag with a front side 30 and a rear side opposite it, which is not visible in the embodiment. The front side 30 and the rear side are connected to one another via a first side wall 32 and a second side wall, the position of which is indicated by arrow 34. The side walls 32, 34 are each formed by side folds 36 and the weakening lines 14, 16 extend across at least 80% of the width a of the front side 30. The area of the side folds 36 is free of the weakening lines 14, 16.

The upper filling chamber closure 8 has a fingertip contact area 38 on its inner side facing the filling chamber, which is formed by a material bevel 40 between a first leg 42 and a second leg, which cannot be seen in the figures but whose position is indicated by the arrow 44, of the bag 2. The first leg 42 extends from the upper weakening line 16 to the material bevel 40 and the second leg 44 adjoins it starting from the material bevel 40. In the state with the opening field 12 of the bag 2 filled with filling material open, the two legs 42, 44 enclose an angle of no more than 135° when the bag 2 is carried by engaging in the opening field 12. This holding position is approximately in Fig.3 shown, where in Fig.3 the bag 2 is additionally held by a second hand underneath the bag 2.

The distance b of the upper weakening line 14 to the material bevel 40 is 30 to 65 mm and particularly preferably 45 to 55 mm. The distance c of the lower weakening line 16 to the upper weakening line 14 is 15 to 25 mm. The peripheral wall 6 of the bag here also has a front side 30 and a back side that is not visible in the exemplary embodiment, with both weakening lines 14, 16 being arranged centered on the front side of the bag 2 and extending over 15 to 35% of the bag circumference.

In the embodiment, the upper filling chamber closure 8 is formed by a transverse seam 46 and the transverse seam 46 also forms the material bevel 40 in the interior of the bag 2.

Fig.4 shows a section of a film tube 48 according to the invention for producing the aforementioned bags 2 according to the invention. The film tube 48 has a plurality of tear strips 10 arranged parallel to one another at constant distances to release an opening field 12, each of which is delimited by an upper weakening line 14 and a lower weakening line 16. The film tube 48 also has a longitudinal seam 18 running along the film tube 48. The upper and lower weakening lines 14, 16 each begin in the area of the longitudinal seam 18 and the longitudinal seam 18 is weaker in the area between the upper and lower weakening lines 14, 16 assigned to a tear strip 10 than above the upper weakening line 14 and below the lower weakening line 16.

In the film tube 48 according to the invention, a flag 22 is arranged at the beginning 20 of each tear strip 10 between the two weakening lines 14, 16 assigned to this tear strip 10, which extends beyond the longitudinal seam 18 in the opposite direction to the tearing direction 24 and does not adhere to the material 26 of the wall 6 of the sack 2. The film tube 48 also has a plurality of material bending areas 52 arranged at constant intervals transversely to the longitudinal extension, shown by the arrow 50 of the film tube 48, for introducing a material bend 40 in each case. The distance b of the upper weakening line 14 of the assigned tear strip 10 to the material bending area 52 is 30 to 65 mm and in particular 45 to 55 mm. The distance c between the lower weakening line 16 and the upper weakening line 14 of each tear strip is 15 to 25 mm. The weakening lines 14, 16 are shown on the film tube 48 in its flat state in Fig.4 , arranged centrally and extend over 15 to 35% of the film tube circumference.

The film of the film tube 48 in the region of the ends 28 of the weakening lines 14, 16 and the film and the width of the tear strip 10 are designed such that the resistance to tearing of the tear strip 10 beyond the ends 28 of the weakening lines 14, 16 is greater than the resistance to tearing of the tear strip 10 from the film tube 48.

Reference numbers

2

bag

4

lower floor

6

Wall

8

upper filling chamber closure

10

Tear strip

12

Opening field

14

upper line of weakness

16

lower line of weakness

18

Longitudinal seam

20

Beginning of the tear strip

22

flag

24

Tear direction

26

Wall material

28

End of the lines of weakness

30

front

32

first side wall

34

second side wall

36

Side folds

a

Width of the front

38

Fingertips on location area

40

Material bending

42

first leg

44

second leg

b

Distance upper weakening line - material bend

c

Distance upper weakening line - lower weakening line

46

Cross seam

48

Film tube

50

Longitudinal extension

52

Material bending area

Claims (11)

1. Bag (2) with a filling space for bulk material which is delimited by a lower base (4), a circumferential wall (6) and an upper filling space termination (8) facing away from the lower base (4), and with at least one tear-off strip (10) to release an opening field (12) of the bag (2) which is delimited by an upper tear line (14) and a lower tear line (16), wherein both tear lines (14, 16) run parallel to the upper filling space termination (8) and the upper tear line (14) is positioned between the upper filling space termination (8) and the lower tear line (16), wherein the bag (2) has a longitudinal seam (18) which opens transversely to the upper filling space termination (8), the upper and the lower tear line (14, 16) begin in the region of the longitudinal seam (18) and the longitudinal seam (18) is formed to be weaker in the region between the two tear lines (14, 16) than above the upper tear line (14) and below the lower tear line (16), wherein the bag (2) is a side gusset bag with a front side (30) and a rear side which are connected to one another via a first side wall (32) and a second side wall (34), wherein the side walls (32, 34) are formed in each case by side gussets (36), and the tear lines (14, 16) extend transversely over at least 80% of the width (a) of the front side (30) or the width of the rear side, in particular over the entire width (a) of the front side (30) or the entire width of the rear side, the region of the side gussets (36) is, however, free of the tear lines (14, 16), and wherein the upper filling space termination (8) has a fingertip bearing region (38) on its inside facing the filling space, which is formed by a material fold (40) between a first limb (42) and a second limb (44) of the bag (2), wherein the first limb (42) extends from the upper tear line (14) up to the material fold (40) and the second limb (44) adjoins this starting from the material fold (40), characterized in that the two limbs (42, 44) enclose, in the state with an opened opening field (12) of a bag (2) filled with filling material when carrying the bag (2) by engagement into the opening field (12), an angle of no more than 135 degrees, and that the distance (b) from the upper tear line (14) to the material fold (40) is 30 to 65 mm, the distance (c) from the lower tear line (16) to the upper tear line (14) is 15 to 25 mm and the circumferential wall (6) of the bag (2) has a front side (30) and a rear side, wherein both tear lines (14, 16) are arranged centred either on the front side (30) or on the rear side of the bag (2) and extend over 15 to 35% of the circumference of the bag.
2. Bag (2) according to Claim 1, characterized in that the bag (2) has a disruptive substance which hinders a welding process in the region of the longitudinal seam (18) between the two tear lines (14, 16).
3. Bag (2) according to any one of the preceding claims, characterized by a flag (22) which is arranged at the start of the tear-off strip (10) between the two tear lines (14, 16), goes beyond the longitudinal seam (18) counter to the tear-off direction (24) and does not adhere to the material of the wall (6) of the bag (2).
4. Bag (2) according to any one of the preceding claims, characterized in that the bag material in the region of the ends (28) of the tear lines (14, 16) and the material and the width of the tear-off strip (10) are formed in such a manner that the resistance to a tearing off of the tear-off strip (10) beyond the ends (28) of the tear lines (14, 16) is greater than the resistance to a tearing off of the tear-off strip (10) from the bag (2) .
5. Bag (2) according to any one of the preceding claims, characterized in that the bag (2) is composed of a film.
6. Bag (2) according to any one of the preceding claims, characterized in that the upper filling space termination (8) is formed by a transverse seam (46) and the transverse seam (46) also forms the material fold (40) inside the bag (2).
7. Bag (2) according to any one of the preceding claims, characterized in that the upper filling space termination (8) is formed by an upper base and the material fold (40) forms the transition of the circumferential wall (6) to the upper base.
8. Film tube (48) for producing bags (2) according to any one of the preceding claims, with a plurality of tear-off strips (10) arranged at constant distances parallel to one another for the release of in each case one opening field (12) which are delimited in each case by an upper tear line (14) and a lower tear line (16), wherein both tear lines (14, 16) run parallel to one another, with a longitudinal seam (18) running longitudinally with respect to the film tube (48), wherein the upper and the lower tear lines (14, 16) begin in each case in the region of the longitudinal seam (18) and the longitudinal seam (18) is formed to be weaker respectively in the region between the upper and lower tear line (14, 16) assigned to a tear-off strip (10) than above the upper tear line (14) and below the lower tear line (16) and with a plurality of material fold regions (52) arranged at constant distances in each case transversely to the longitudinal extent (50) of the film tube (48) for incorporation in each case of a material fold (40) which is assigned in each case to a tear-off strip (10), wherein the distance (b) between the upper tear line (14) of the assigned tear-off strip (10) and the material fold region (52) is 30 to 65 mm, the distance (c) between the lower tear line (16) and the upper tear line (14) of each tear-off strip (10) is 15 to 25 mm and the tear lines (14, 16) on the film tube (14), in its laid-flat state, are arranged in a centred manner and extend over 15 to 35% of the circumference of the film tube.
9. Film tube (48) according to Claim 8, characterized in that the film tube (48) has a disruptive connection which hinders a welding process in the region of the longitudinal seam (18) in each case between the upper and lower tear line (14, 16) assigned to a tear-off strip (10) .
10. Film tube (48) according to any one of preceding Claims 8 or 9, characterized by a flag (22) which is arranged at the start of each tear-off strip (10) between the two tear lines (14, 16) assigned to this tear-off strip (10), goes beyond the longitudinal seam (18) counter to the tear-off direction (24) and does not adhere to the material of the wall (6) of the film tube (48) .
11. Film tube (48) according to any one of Claims 8 to 10, characterized in that the film of the film tube (48) in the region of the ends (28) of the tear lines (14, 16) and the film and the width of the tear-off strip (10) are formed in such a manner that the resistance to a tearing off of the tear-off strip (10) beyond the ends (28) of the tear lines (14, 16) is greater than the resistance to a tearing off of the tear-off strip (10) from the film tube (28).

Images