Patent Application
20150336713
The present invention relates to film bag. More particularly this invention concerns such a bag with a handle.
A typical film bag is formed by a front panel and a back panel each having an inner face and an outer face. The outer faces of the front panel and the back panel form the outer surface of the film bag. The film bag is preferably designed for dry bulk solids. It features a fastener that can be reclosed after an initial opening.
A film bag with these characteristics is known from EP 0 843 636 (U.S. Pat. No. 5,823,933). The film bag has a pull tab arranged in the front panel. On the back side of the opening formed by the pull tab a reclosable fastener is attached in such a manner that a so called “arm” of the reclosable fastener spans across the opening. Thus the opening can be sealed by the reclosable fastener. In one particular embodiment a second arm of the reclosable fastener extends to the side of the reclosure tab remote from the opening. There it is attached to the inner face of the front panel by a peelable seal. This provides an additional tamper-evident closure for the bag and improves stability of the reclosable fastener after having been opened.
It is one key disadvantage of the known film bag that it cannot be emptied easily. The contents of the bag can only be poured in single direction. In the opposite direction, the bag material may be held back by the reclosable fastener.
Furthermore, the known bag forms a straight opening which is difficult to handle. The edges of this straight opening have to be separated in a way that is cumbersome, especially with a bulging bag. In addition the space behind the opening defined by the reclosable fastener and its leg is open to the sides. Welding on the sides is challenging during automated production. Therefore the sealing properties of the prior art bag are inferior.
EP 2 535 292 shows a pour spout arranged in a side gusset of a film bag. For pouring the spout can be folded outward. An additional film panel is on the inside of the film bag, partially behind the pour spout. The film panel carries one half of an reclosable fastener whose other half is on the inside of the pour spout.
The sealing properties according to this second prior art are somewhat better, yet the same disadvantages concerning an opening defined by two parallel linear edges apply as well.
It is therefore an object of the present invention to provide an improved film bag.
Another object is the provision of such an improved film bag that overcomes the above-given disadvantages, in particular to improve the properties of a reclosable film bag in order to facilitate the withdrawal of bulk goods stored inside the film bag and improve the sealing properties of the reclosure.
A film bag has according to the invention a front panel and a back panel having confronting inner faces and outer face forming an outer surface of the film bag. An inner cover patch between the front and back panels has a front face confronting the back face of the front panel. A continuous frame weld, preferably of rectangular shape, secures the inner cover patch to the inner face of the front panel. A first cut or weakening line in the front panel within an area bounded by the frame weld defines all but one side of a flap that is also preferable rectangular and that is connected unitarily as a hinge at the one side to the front panel. A reclosable fastener is provided between the front face of the patch and the inner face of front panel, and a direct attachment between the fastener and the hinge directly connects the front face of the flap to the inner face of the front panel. A second cut or weakening line is formed in the inner cover patch between the direct attachment to the flap and the recloseable fastener so that outward pivoting of the flap of the front panel about the hinge separates the reclosable fastener and pulls out a portion of the patch between the second line and the attachment. Stops, for instance cross welds or circular holes, may be provided at the end of the cut/weakening lines to limit separation of the plastic sheets forming the panels and patch. The direct attachment is preferably formed as a continuous patch or one or more dots. A single weld dot is preferably centered close to the second cut or weakening line.
Preferably according to the invention either the first cut and/or weakening line or the second cut and/or weakening line do not go all the way through the respective plastic sheet in order to initially provide a completely air- and liquid-tight film bag.
In a preferred embodiment a reclosable fastener is a strip fastener, in particular a hook and loop fastener. In another preferred embodiment the reclosable fastener is formed by interlocking and complementary profile strips that can be pressed together. Any other reclosable fastener technique known may be incorporated into the present invention.
It is also preferred that the reclosable fastener is adapted to conform with the outline of the flap. Thus it is possible to attach the flap up to its edges which leads to better sealing properties. The reclosable fastener may be preformed prior to the application on the film bag. Alternatively, it may be provided as an element extending beyond the flap and being incised conforming to the cut or weakening line in the front panel.
It is preferred that the front panel and the back panel of the film bag have weldable inner faces and that the bag be assembled by heat sealing.
It is especially preferred that the inner cover patch also has a weldable surface turned toward the inner face of the front panel. What is more, the frame weld and/or the direct attachment between the flap and the inner cover patch are formed by thermal welds. During production, it may be advantageous to first apply a reclosable fastener according to the invention to the front panel and form a film bag from this prepared front panel afterward.
In addition, the frame weld or the direct attachment between the flap and the inner cover patch can be formed by an adhesive.
It is preferred that the bag has side gussets provided between the front panel and the back panel. The side gussets are usually formed by two additional film panels that are fixed to the front panel and the back panel by longitudinal weld lines. Side gussets increase the capacity of a film bag and a lead to a more stackable shape when the bag is bulging and full.
It is also preferred that the flap has a grip portion arranged at the opposite side of the reclosable fastener seen from the hinge section. The grip portion is not held at the inner cover patch by the reclosable fastener or any other connection. It is freely accessible to the user.
To that end, it is especially preferred that the grip tab of the flap is defined by a full cut whereas the rest of the flap is defined by a weakening line. Through this, it can be accessed by the user without tools or major effort.
It is preferred that any one of the weakening lines is formed by a perforation, a score or a laser score.
In a preferred embodiment, the second cut or weakening line provided on the inner cover patch forms an inner flap surrounding the direct attachment and offset inward from the outer edge of the first, outer flap. The direct attachment between the inner end and the outer flap ensures that both flaps open and close simultaneously. The offset between the edges of both flaps leads to a very tight reclosure since the gap of the opening is elongated and guided in the plane of the front panel between the back side of the front panel and the front side of the inner cover patch.
The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
As seen in
According to the invention, a rectangular inner cover patch 8 is connected to an inner face 9 of the front panel 3 by a continuous rectangular frame weld 10. The frame weld 10 is formed thermally.
A flap 11 is formed by a cut line 12 and two adjoining weakening lines 13 in the material of the front panel 2 surrounded by the frame weld 10. The full cut 12 defines a grip tab 14 of the flap 11 whereas the rest of the flap 11 is defined by the weakening lines 13 formed by rows of perforations. The ends of the weakening lines 13 away from the grip tab 14 are terminated by circular cuts 15 forming tear stops. The flap 11 is of generally rectangular shape with a lower side formed by the cut 12 of the grip tab 14 and adjoining parts of the weakening lines 13, two generally vertical sides made of the rest of the weakening lines 13 and a horizontal hinge 16 formed by the top of the flap 11 made from uncut and unperforated material of the front panel 2 between the two tear stops 15.
In addition, a strip fastener 17 is provided between the flap 11 and a corresponding face of the inner cover patch 8. The flap 11 is directly attached at 19 to the inner cover patch 8 between the hinge 16 and the reclosable fastener 17. In the inner cover patch 8, a second cut or weakening line 18 is provided between the direct attachment strip 19 of the flap 11 and the reclosable fastener 17. The second cut or weakening line 18 forms an inner second flap 20 like the outer first flap 11 but offset inward therefrom.
The outline of the reclosable strip fastener 17 in a planar view is adapted to conform with the outline of the flap 11. The fastener 17 stretches across the full width of the frame weld 10 and extends parallel to the lines 12 and 13 of the outer flap 11. The fastener 17 can be a pair of press-together complementary strips or a hook-and-loop fastener.
A comparison of
