DK148415B - PLASTIC SEARCH WITH A FILLING VALVE - Google Patents

Description

χ 148415 o

The present invention relates to a plastic bag with a filling valve and of the kind specified in the preamble of claim 1.

Plastic bags of this kind are known, among other things. from German Patent Specification No. 1,949,086 and from German Publication No. 1,536,135 and is distinguished by the fact that the air during the filling of the bag can escape unobstructed from it, and without this entails e.g. powdered material which is filled into the bag.

A disadvantage of these known sacks, however, is that due to the smooth surface of the plastic material, they are difficult to grasp and handle, which in particular causes labor problems when they have to be manually removed from the filling nozzle of a sack filling machine after filling.

The object of the invention is to overcome this disadvantage and to provide a plastic bag of the kind in question which, in addition to the air during the filling of the bag, can escape unobstructed from it particularly easily and can be removed from the filling nozzle of a bag filling machine.

This object is achieved with a plastic bag which is configured as defined in the characterizing part of claim 1.

In this design of the bag, after filling it can be conveniently grasped and removed from the filling valve by inserting a hand into the pocket until the hand reaches the bottom thereof. This ensures a good firm grip in the bag and can easily remove it from the bag filling machine and handle it, regardless of whether the bag exterior is smooth and prone to slip in the hand.

In order to obtain a particularly sturdy roof of the bag, pockets should be suitably deep, and it is therefore preferred that the pocket extends at least to the inner edge of the corner tab and preferably past said inner edge of the corner tab.

The pocket may consist of a nonwoven thermoplastic material, preferably polyester fibers.

2 148415 d

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail from an embodiment, with reference to the drawing, in which: FIG. 1 schematically shows a portion of a plastic bag with 5 a filling valve according to the invention; FIG. 2 schematically shows a portion of a plastic bag comprising a gas-permeable layer placed opposite the filling valve in the form of a nonwoven pocket; FIG. 3 is a bottom view of a sack provided with a filling valve and a gas permeable pocket similar to that of FIG. 1 and 2, and FIG. 4 is a cross-section through a filling valve and a gas permeable layer in a bag similar to that of FIG. 3.

FIG. 1 shows a plastic bag 1 comprising a front foil layer and a rear foil layer which together form one. tubular film of e.g. polyethvlenfoliemateriale.

The sack 1 is provided with a bottom 2 formed by a first bottom tab 3 and a second bottom tab 4 which are interconnected by an adhesive connection or a welding connection 5.

The first and second bottom tabs 3 and 4, respectively, present a bottom tab edge 8 and 9.

During the formation of the bottom, the first and the second corner tabs 11 and 12 are formed simultaneously. The first corner tab 11 is provided with a first corner tab edge 14 which is located inside the bag. The second corner tab 12 is provided with a second corner end edge 13.

After forming the corner tabs 11 and 12, a plastic valve tube 6 is placed on the first corner tab 11. Preferably, an inner end portion 16 is folded backward toward the protruding end 17 of the valve tube 6, and this portion 16 is attached to the first corner tab 11 and a foil layer 21. , which covers the bottom.

35 3 U8415 o

The valve tube 6 is a filling valve 18 which is located within the bag and extends further into the bag than the corner flap edge 14 of the second corner flap 12.

The free end edge 17 of the filling valve tube 6 projects 5 outside the interior of the bag. By means of adhesive joints or heat seals 19 and 20, the valve tube 6 is connected to the corner tab 11 and to a foil layer 21 which covers the bottom and which is fixed along the folded bottom tabs 3 and 4. On top of the second corner tab 12, a pocket 22 of gas permeable material of such length that it extends past the inner end edge 13 of the second corner tab 12 inside the bag.

Near the free outer edge 23, the pocket 22 is attached to the bottom foil 21 which covers the bottom tabs 1S 3 and 4 folded in a direction toward each other and the portion of the second corner tab 12 located directly below it by means of of an adhesive or a heat seal.

It will be appreciated that the fine material filtering, 20 gas permeable pocket 22 allows a gas or air which has been used for filling and is now enclosed in the bag to escape as the interior of the bag is now connected to the exterior through the gas permeable pocket. 22. This gas-permeable pocket 22 comprises layers 22a and 22b, the edges of which 25 are interconnected or integral with one another, thus forming said gas-permeable pocket 22.

After filling the bag by means of a filling machine, under which the bag hangs from the filling machine, via the filling valve 6, the bag can easily be removed from the filling machine, e.g. by inserting a hand into the pocket 22, whereby the plastic bag, which in itself is very smooth, can be easily grasped and removed from the filling machine.

For this purpose, the mouth 26 is opened by the pocket 22, after which a hand can be inserted into the pocket 22 until it reaches the bottom 15 of the pocket 22. As can be seen, the bottom 4 extends

14841S

o 15 of the pocket is inside the bag past the edge 13 of the second corner tab 12. The second corner tab 12 and the foil 21 covering the bottom are unable to touch each other to ensure optimum removal of gas 5 or air . The bottom 15 of the pocket forms the gas-permeable connection between the two layers 22a, 22b.

As can be seen, the adhesive strip parts or heat seals 24 and 25 connect the layer 22a of the pocket with the inner side of the inwardly folded portions of the bottom tabs 24a, 10 24b and with the cover film 21 and layer 22b with the corner tab 12.

To fill the bag, the mouth 10 of the filling valve 6 is opened. 3 shows that the adhesive strip parts or heat seals 20a and 20b are located between the tubular valve film 6 and the inside of the inwardly folded portions of the bottom tabs 3 and 4. In order to avoid loose portions of the covering bottom layer 21, the end region 27 of the cover layer 21 is completely connected to the the valve tube 6 over its entire length in a flattened state.

If desired, the cover layer 21 can be omitted and the bottom 20 can be formed by providing the tubular bag foil with the incision and folding bottom tabs as described in British Patent Specification No. 1,072,856.

It should be noted that the bag according to the invention is very advantageous in that the strength of the wall of the bag is not degraded by using the gas permeable layer. This is mainly due to the fact that the gas permeable layer is covered by the bottom portions of the bag.