Flexible Container

The present invention relates to a flexible container, especially of a carrier bag, produced of a nonwoven material, preferably of a spunbonded material.

It is known that carrier bags flexible containers, typically carrier bags, can be present in particular in grocery shops stores or similar high street department stores for the use of carrying goods home. Usually, these carrier bags are made of PE film that are typically disposable in design and specification.

It is also know that as an alternative to the disposable film based products reusable bags have been implemented by retailers as an environmentally improved product of choice. Typically these products are hand made from robust material such as woven Polypropylene.

It is an object of the present invention to provide a flexible container which will not be elongated as much as, for example, a carrier bag made of film.

This object is achieved by means of a flexible container having the features of claim 1 as well as by means of a method of manufacturing having the features of claim 44. Further preferable embodiments and developments are specified in the respective sub-claims.

The flexible container according to the invention, preferably a carrier bag, comprises as a side wall at least one sheet-like nonwoven web and ahas an opening and an adjacent base. The flexible container comprising an opening, preferably a filling opening, of non- woven and a base of nonwoven fabric opposite the opening is preferably being provided with a handle. The following several embodiments are explained based on a flexible con- tainer.|The flexible container is preferably a ^' carrier bag or any other sort of bag distributed in shops.

According to one embodiment, the whole flexible container is made of nonwoven fabric. Preferably, the flexible container comprises a first and a second side wall which are arranged opposite one another. Preferably, both are formed from the same nonwoven web. Preferably, the filling opening is also made from the same shest-like nonwoven web with the bottom being preferably generated from the same sheet-like nonwoven web. The han-

die can be arranged in the side wall. However, there is also the possibility that one or several handles, preferably two handles are attached to the respective side walls.

According to one embodiment, the handle is made of a nonwoven fabric. Preferably, the handle is in the shape of a loop-shaped handle and connected to the side web by force- fitting. For example, a bond can be effected through welding. This can be effected through thermal softening, in particular by starting a melting process or by means of ultrasound. According to another embodiment, the handle is made of a a nonwoven fabric which is different from the sheet-like nonwoven web which forms at least the major part of the flexible container. For example, the nonwoven fabric of the handle can have a higher weight per unit area than the weight per unit area of the sheet-like nonwoven web. There is also the possibility that another polymer is used for manufacturing the nonwoven fabric for use as handle material. According to a further embodiment the handle is provided in a drawer tape manner, whereby the drawer tape is produced of a nonwoven material, a film, a rope and/or an other suitable material.

Preferably the handle as well as the container are intended to be manufactured via an automated machine process. The container being provided preferably with a single or plurality of handles or like devices for the preferable intention of providing a means of con- taining goods to be purchased from or provided through a retail outlet. A carrier bag comprising a filling opening and a bottom opposite said filling opening with the carrier bag is preferably provided with at least one handle. An automated production allows to increase the manufacture speed, to reduce high cost due to the labour content of manufacturing process costs and implement automatic control systems which survey the manufacturing quality, preferably not only of the nonwoven material used but also of machining steps like welding.

The handle can be integrated into the container or can be attached to the container itself. In difference to containers such made from films the proposed flexible containers have a lower degree of flexibility and do not expand to an extraordinary extent when subjected to force. Using automatic processes for nearly all production steps allow to make available an efficient machine madecarrier nonwoven reusable bag which on the one hand has high strength and durability in conjunction with the benefits of a soft feel produced with the economical benefits of automated production.

According to one embodiment it is possible that the predominant component of the flexible container is made of polypropylene, a polymer containing polypropylene and a copolymer respectively as well as of a bicomponent and multicomponent material respectively. By contrast, the handle material can be made up of a polymer containing polyethylene, pref- erably a bicomponent material such as, e.g. a sheath-core fiber. Preferably, the bicomponent material comprises, at least partly, preferably over the whole area, polyethylene at the surface whereas a different polymer, preferably polypropylene, is arranged inside. Thus, the polypropylene can exhibit high strength whereas the polyethylene is suitable to provide an especially pleasant wearing comfort on the skin. According to another em- bodiment the predominant polymer used for the nonwoven material is based on a polyethylene.

According to a further embodiment, the flexible container.features handles of different lengths. For example, two handles of equal length are provided which the carrying person can grip. Moreover, it is possible that an additional handle is provided which is much longer. Thus, the flexible container can be carried, e.g. with the shoulder. For this purpose, the longer handle can provide a broader carrying area than the handle for carrying by hand.

■ Preferably, the sheet-like nonwoven web extends in CD direction from the filling opening towards the bottom with the direction of the nonwoven fabric comprising a higher tensile strength in MD direction than in CD direction. Thus it is made sure that with respect to direction in which the nonwoven fabric is able to withstand the least strain, it is subjected to the greatest strain when the flexible container is filled. Thus it can be very easily ascer- tained whether the items packed into the flexible container exceed an admissible weight. Due to the special arrangement of the sheet-like nonwoven web it is prevented that following the initial start of the transport it is ascertained only during transport that too much was arranged in the flexible container. Usually, re-sorting into one or several other flexible containers is then no longer possible.

Another further development provides for the sheet-like nonwoven web to extend from the filling opening towards the bottom in MD direction with the nonwoven fabric comprising in CD direction a higher tensile strength than in MD direction.

According to another embodiment the flexible container comprises an excessive load safety device. By means of the excessive load safety device it is made sure that the flexi-

ble container is not made heavier by filling than it should be. The excessive load safety device can, for example, be formed by a safety strip arranged on the flexible container. This safety strip tears if a maximum load is exceeded. As the function parts of the flexible container themselves, such as in particular the handles, continue to be available, the flexible container can still be used after it has been emptied. Thus, it can be immediately ascertained whether also for a longer transport by means of the flexible container the tensile strength is sufficient.

According to a further development the nonwoven web comprises an increased tensile strength resulting from embossing. An embossed area preferably forms between 10 % to 70 % of the area of the nonwoven web, in particular between 15 % and 30 % with, preferably, a single embossed area having a size of between 0.05 mm ² and 3 mm ² . Preferably, embossing is carried out through a thermo-bonding step. Embossing is, in particular, such that the tensile strength of the nonwoven web is increased more in MD direction than in CD direction. It is, for example, provided that a main axis of an embossing region is arranged in CD direction.

Embossing, in particular thermo-bonding, is preferably effected by means of an embossing calender which comprises suitable elevations. A plain roller and an embossing roller form, for example, a calender nip with at least one of the two rollers being heated to a temperature which effects, in particular, that the nonwoven fabric fed through the calender nip starts to melt. In addition to embossing through the effect of heat, there is also the possibility to effect a densification of the nonwoven fabric by appropriate other means, such as, e.g. ultrasound, heat radiation, hydroentanglement and/or the use of adhesives such as adhesive fibers or the like. The nonwoven web, in particular the side walls opposite one another are interconnected in at least one area, in particular welded together. It has proved to be advantageous if at least the material in a welded area, preferably when creating an edge, is a co-polymer. The co-polymer can comprise, e.g. polypropylene and polyethylene. Using the co-polymer effects an improved material bonding in the case of welding. When using a PP and/or PE, in the case of ultrasonic welding, a frequency in an area between 10,000 to 30,000 Hz is preferably used to impart the energy to the material.

A bonding of ends of a nonwoven web can, for example, be effected by overlapping. For this purpose, broad areas can, for example, be welded together. Another possibility is that edges arranged opposite one another are arranged to form a butt joint. Nonwoven material and polymer material can be added, for example, in order to enable the joining of the

nonwoven web. A joint of the nonwoven web can, for example, be arranged in the area of a side wall. However, there is also the possibility that the joint is arranged in a transverse side of the flexible container. According to another embodiment, there is or there is no joining of nonwoven fabric in the bottom area. For this purpose, for example, the non woven web or other nonwoven fabric can be brought up in a side wall or a transverse side of the flexible container in order to effect there the joining of the nonwoven materials.

Joining can, for example, also be effected by using a film material. Such film can, for example, make available an additional polymer material which, additionally, is also used in the area of the seam formation. In addition to welding, gluing together or other bonding techniques can be employed in addition to or in the stead of welding.

In addition to bonding one or several sheet-like nonwoven webs for generating a carrier web, the nonwoven material is coated, preferably either before or afterwards. For exam- pie, an additional film can be arranged inside the flexible container. However, it is also possible that the film is arranged outside. In particular, a laminate can be used for manufacturing the flexible container. In this case one or several nonwoven fabrics and films respectively can form such a laminate. It is preferably provided, however, that the flexible container is essentially completely made up of nonwoven fabric and that the flexible con- tainer consists, if possible, for the most part, in particular nearly completely of a one-ply nonwoven fabric. Furthermore, it is possible that a side wall of the flexible container, in particular a nonwoven web, features a barrier effect. The side wall, for example, presents such a barrier that it is permeable to water vapour and impermeable to water with the nonwoven web preferably comprising a column of water of at least 100, especially of at least 200 mm, preferably up to 1000 mm. For this purpose the nonwoven web can, for example, have a particular build-up, for instance as meltblown-spunbond-laminate. It is also possible to use, for example, a microporous film or a diffusion film with the nonwoven fabric. The side wall, in particular the nonwoven web, is permeable to air. Air permeability is preferably in a range between 1000 to 5000 l/m ² /sec, preferably between 2000 to 3000 l/m ² /sec. Therefore, the flexible container thus manufactured is especially suitable for transporting foodstuffs as well as for transporting other products for which an exchange of air is necessary.

In addition to being used in particular for purposes relating to foodstuffs, the suggested flexible container can be used in other areas, too. The flexible container can, for instance, have thermal insulation. For this purpose, a nonwoven fabric is, for instance, manufac-

tured comprising a particular porosity and particular thickness. Due to the air pockets in the nonwoven fabric, heat insulation is possible towards the outside having the effect that chilled products arranged in the flexible container are longer at a minimum temperature than outside of the flexible container. This can be enhanced by equipping a flexible con- tainer put to such use, for example, on the inside and/or outside with a coating, e.g. an aluminium coating or a similar metal lining preventing the exchange of heat. In addition, there is also the possibility that heat insulation is attained by providing the nonwoven fabric with a film on one ore both sides. In the latter manner, the volume of the nonwoven fabric is locked in, serving wholly as heat insulation. An exchange, which might be neces- sary, from the inside of the flexible container to the outside and vice versa can be effected through a preset porosity of the film material. It is also possible that the film is partly, preferably completely, impervious to fluids and vapour. Furthermore multiple layers of similar or differing materials might be used to achieve a plurality of wall sections to be advantageously used as a cool bag or for the benefit of end product protection.

According to another embodiment, at least one of the side walls, preferably both side walls of the flexible container have a print. For this purpose, the side wall can, preferably, comprise one or more coats. It is also possible that the side wall comprises a relief. Such relief can, for instance, be effected by suitable embossing. A targeted change to the sur- face of a side wall in certain areas can, for example, be effected through the impact of heat. By generating such relief and supported by print a special effect can be obtained. The material might be printed with a graphical image in an inline automated process. The material might be printed with a graphical image in an inline digital process.

According to another embodiment, the flexible container is reusable. It can, for example, be washed. For this purpose the flexible container can be hydrophobic so that after cleaning a dry flexible container is on hand very quickly. The flexible container can also be dirt- repellent. This can be effected by, e.g. adding an additive with the polymer of the non- woven material. However, it is also possible to apply an appropriate dirt-repellent layer.

It has also proved to be advantageous if reinforcement is provided in the area of the bottom. The reinforcement can, for instance, be effected by an insert which, in particular, also imparts its shape to the flexible container. The reinforcement can be flexible or rigid. It can consist of one or several layers. The reinforcement material can be a plastic and can, in particular, be of the polymer the nonwoven fabric is made of. Furthermore, it is also possible that a nonwoven fabric is used as reinforcement. Furthermore, it is possible to also

provide reinforcement in the handle region. Here, a reinforcement of the handle can on the one hand offer an area of a joint between the flexible container itself and the handle. For example, an additional material can be provided which enables a connection with a material pertaining to the handle. It is also possible that the reinforcements prevents that the handles from tearing off. For this purpose, the reinforcement can additionally be connected each to the handle and a side wall. It is also possible to provide a reinforcement in the area of the handle region itself. Such reinforcement can, for instance, be obtained by broadening the handle region which prevents that the handles cut into the palm. A reinforcement is also used in order to enable a broadening of the working area of the handles for carrying and, at the same time, for finding support in one hand. For this purpose the reinforcement can, be made of, e.g. cardboard, paper, foam material or the like.

According to another embodiment of the flexible container it consists at least partly, preferably for the most part and in particular completely of a biodegradable polymer. Prefera- bly, a nonwoven fabric is for example employed which degrades when exposed to long sun radiation and/or oxygen supply. The polymer used can, for example be able to be composted, so that after using it the flexible container can be included in the normal rubbish. There is, in particular, also the possibility that the flexible container after using it, i.e. transporting items, can also be used for storing waste for an organic waste bin. The flexi- ble container can, e.g. be used as a liner for an organic waste bin as it is used in the household. A polymer based on starch is, for instance, suitable.

It is particularly preferred if the nonwoven fabric comprising the nonwoven web comprises a metallocene polymer. The metallocene polymer can be a homopolymer. However, a blend with other polymers is also possible.

According to another embodiment, the nonwoven web comprises a nonwoven fabric with a polymer which comprises at least several of the following members of the group comprising PO, PET, biodegradable polymer, PP, PE, copolymer, antimicrobial additive, hy- drophilic additive, phosphorescent additive, fluorescent additive, antistatic additive and dirt-repellent additive.

According to another embodiment of the invention, a seam of the side wall has a seam strength preferably up to 250 N/5cm, especially between 60 and 150 N/5cm. A seam of the side wall preferably has a seam elongation between 10 % and 450 %. A handle of the flexible container preferably comprises a tensile strength of at least 10 N, more preferably

in the range of 40 to 100 N, especially around 55 N. An elongation of the handle ranges preferably between 10 % to 450 %, especially between 20 % to 40 %.

According to another thought underlying the invention a method for manufacturing a flexi- ble container using a nonwoven web is made available with the nonwoven web being folded in CD direction and sides of the nonwoven web lying opposite one another are made into side walls of the flexible container with the nonwoven web being processed in a manner that the nonwoven web extends in MD direction from a bottom of the flexible container towards a filling opening. Thus, it is made sure that when the flexible container is later put to use, any overloading in particular due to the packing of too many items into the flexible container resulting in bursting on the sides is prevented. In particular on designing the flexible container in such manner, attention is turned to that on lifting the flexible container the tensile strength must always be sufficient. Through appropriately arranging the nonwoven web it is made sure that the tensile strength prescribed for the material never falls below the minimum tensile strength as it defines, at the same time, the stipulations for the specification of tensile strength for lifting the flexible container.

According to a preferred embodiment as regards the flexible container and its manufacture, a nonwoven web is used having a weight per unit area of preferably at least 5 g/m ² , more preferably at least 25 g/m ² , in particular at least 40 g/m ² , preferably between 40 g/m ² and 60 g/m ² , comprising a polypropylene spunbond nonwoven web with seams for connecting the nonwoven web for generating the side walls being generated through welding, and with at least one handle being welded to a side wall, in which case as material for the handle a spunbond fabric is preferably used having a weight per unit area of preferably at least 10 g/m ² , at least 70 g/m ² , preferably between 80 g/m ² and 100 g/m ² .

The flexible container can comprise one or several layers of nonwoven. Here, one kind of nonwoven fabric or different kinds of nonwoven fabric can be used. According to one embodiment, for example a spunbond nonwoven, a carded nonwoven-, SMS material, a film- nonwoven-laminate, an airlaid material, a spunlace material, a meltblown material, an elastic nonwoven, a bicomponent material and/or a nonwoven is used the fibers and filaments respectively of which feature specific geometries, for instance are trilobed or have other geometries, in particular those which are of no round shape in their cross section.

According to another embodiment, an additional pocket is arranged on the flexible container. It can, for example, serve as a means of transport for keys or similar small items.

This small pocket can, for example, be formed by an attachment which is glued on or welded on. At the top the additional pocket can be open or able to be closed. For example, by means of Velcro® fastener it can be made sure that no items are lost out of the additional pocket. Furthermore, it is possible that the filling opening of the flexible con- tainer is also able to be closed. For example, for this purpose a Velcro® fastener or other possibility can be generated in order to enable repeated closing and opening of the filling opening. For this purpose the flexible container can, for example, feature an overlapping area which is folded over the filling opening itself and through which one or several handles of the flexible container can be driven. Such overlapping area is formed, for example, by a side wall the area of which is longer than the one of the side wall opposite. Flapping it over closes the filling opening. This prevents, for example, the seeping-in of fluid, in particular rain.

Furthermore, when manufacturing the flexible container a co-polymer, such as e.g. a DAPP is used for generating the nonwoven web. For instance, as DAPP material blends can be used mentioned in US 5,804,286, reference to which is made within the framework of the disclosure. A blend of polyethylene and polypropylene to which a compatilizer, e.g. a Cattalloy of Adflex, is added is preferably used. The DAPP enables increased elongation by which a damping of force peaks in the area of a seam, in particular a weld seam of a nonwoven web is made possible. Furthermore, it is preferably provided that, in particular in the area where side edges are joined together, e.g. through welding, an elongation is provided which is increased in comparison to the remaining area of the nonwoven fabric. This can, e.g. be provided by appropriately designed embossing or by an appropriately designed welding edge. Here the material used in the area of the welding edge can have a cushioning and damping effect respectively. The material used here is more elastic and better able to be elongated than in the other areas of the flexible container. Preferably, a seam is not straight-lined from one end to the other. It rather features a structure which changes direction several times, is of a wavy zigzag structure or features other courses. As a result, a larger, in particular longer seam and thus a stronger connection is gener- ated.

A further container as suggested has a line of severance between each container, especially bag, in the web, for the intention of providing a continual number of detachably adjoined containers for advantageous use in a dispensing scenario in a user environment. A container's opening is preferably not parallel to the base. A container's opening is formed according to an embodiment as a curve or sine wave. Any part of the web structure may

have advantageously formed zones of permanent or semi permanent bonding between layers or fibres for the creation of 3-dimensional structures or corresponding forms to the end containers contents.

Other advantageous embodiments and further developments are explained in more detail by means of the following drawings. However, these drawings are not to be considered as limiting. In order to generate further embodiments the features shown can be linked to other features which follow from the drawings as well as with the features described above. Shown are:

Fig. 1 an example of an embodiment of a first flexible container, in particular of non- woven fabric,

Fig. 2 an example of an arrangement of a nonwoven web from which a flexible container is subsequently manufactured, Fig. 3 a further embodiment of a flexible container comprising a nonwoven fabric, Fig. 4 a first further development of a possible design for a handle, Fig. 5 a sectional view through a possible handle,

Fig. 6 a schematic illustration of a device for manufacturing a flexible container, Fig. 7 a schematic view of a print station.

Fig. 1 shows as an exemplary embodiment a first flexible container 1 having a first side wall 2 and a second side wall 3. In this embodiment, both side walls 2, 3 are connected to one another through a first transverse wall 4 and a second transverse wall 5. The walls form a filling opening 6 of flexible container 1. A bottom 7 is, for example, arranged oppo- site the filling opening 6. Bottom 7 can be smooth or vaulted with the vault being concave or convex. A concave vault of the bottom 7 is drawn in a broken line. The first side wall 2 and the second side wall 3 preferably each feature a handle 8. The handle 8 preferably comprises a first end 9 and a second end 10. The ends 9, 10 are connected to the side wall. The ends 9, 10 can be directly or indirectly fastened to the side wall. For example, the ends 9, 10 can be connected to fastening areas 11. The fastening areas 11 themselves can be glued to the side wall or can be welded on or fastened through material- fitting or force-fitting. The fastening areas 11 are preferably also made of a polymer, preferably a polymer which can enter into a combination with the material of the side wall. In addition to handles 8, which are arranged on side walls 2, 3, the flexible container 1 can also comprise one or several handles 8 which are fastened to the transverse walls 4, 5. For instance, handles of various lengths can be provided. Preferably, at least two handles

8 are provided which have the same length and which on carrying effect that the filling opening is closed. In addition, it can be provided that the filling opening 6 can at least be partly closed by means of a closing mechanism 12 which is shown schematically. For example, one or several adhesive strips which enable, in particular repeated closing, can be used for this purpose. It is also possible to provide hooking-in through a Velcroθ-fastener. In this case it is possible to design the nonwoven fabric in the area of the closing mechanism 12 with loop-shaped courses. One possibility follows from DE 197 22 748 A2 reference to which is made in its entirety in the framework of the disclosure with respect to the fastener. On closing, the two side walls 3, 4 are preferably brought to lie on top of one another with the transverse walls - if there are any - preferably moving inside. Furthermore, it is possible that at least one side wall comprises a lengthening 13. Preferably, the lengthening 13 consists of the same material as the side wall. It can, in particular, be folded over in which case it the covers filling opening 6. In particular the lengthening 13 features such dimensions that it covers not only the filling opening 6 but also overlaps the side wall opposite and, preferably, the respective transverse wall. In this manner sufficient sealing of the contents of the flexible container is achieved, in particular against wetness from the top. The lengthening 13 is preferably equipped to be water-repellent. The lengthening 13 can, in particular, also be arranged as an additional element on flexible container 1. It is also possible that the lengthening 13 is provided as an individual item in addition to flexible container 1.

It further follows from Fig. 1 that the flexible container 1 is preferably made of a single material layer. This material layer is preferably folded in such manner that the shape of flexible container 1 can be obtained with few folds. The edges 14 resulting from folding are connected to adjacent areas, preferably the walls. The connection can, for instance, be effected by a broad bonding by means of material-fitting, preferably by welding. For this purpose welding can be carried out by starting a melting process as well as by welding through ultrasound. Welding is preferably carried out not only along the edge 14 but also along a broad area around edge 14. For this purpose the materials are preferably ar- ranged so that they overlap. Welding can be carried out in the inside of flexible container 1 as well as on the outside of flexible container 1. An edge 14 can run lengthwise as well as in transverse direction. It is, in particular, also possible to have an edge running diagonally provided that appropriate folding of the material layer is carried out. It is preferred that edges 14 are arranged at a distance from side edges of the walls that meet. An edge 14 can, e.g. be arranged at a distance of at least 5cm from such a side edge. It is furthermore preferred that on creation of bottom 7, folding is such that a fastening of the folded mate-

rial is effected, as entirely as possible, on a side wall. For this purpose the material is brought up from the bottom in the direction of filling opening 6 along the side wall and arranged on and fastened to it. Fastening can here be effected as a longitudinal sealing and/or transverse sealing. Shown is a longitudinal sealing. Apart from a simple fold the material can also feature multiple folds. In this manner, the forming of loose edges on flexible container 1 through the material layer is prevented. Preferably, all edges that are formed of the material layer of flexible container 1 are connected to the same, preferably by welding, gluing or other means for bonding the material. However, the material layer 15 cannot only be one-ply but can also comprise several layers.

Fig. 2 shows a possible procedure of how to use a material layer 15 for manufacturing a flexible container. The material layer 15 is, for example, fed from an unwind to an appropriate layering device 16 from which a section is shown. The material layer 15 can, as is shown here, for example be fed via appropriate guides 17 in an overlapping manner. The material can be cut after an overlap has been effected. Folding can take place subsequently so that the material layer finally takes the shape of a flexible container following the connection of the overlapping areas. For example, folding takes place in CD or MD direction only in order to effect the overlap. It is also possible that a part of a fold is, at least essentially, effected in CD direction and another part of a fold is, at least essentially, effected in MD direction.

According to another embodiment, for example, the material layer 15 is arranged in an overlapping manner and cut. However, instead of subsequently folding, in particular, border areas, these border areas are directly welded to one another. Thus one or several process steps resulting due to the folding of the material layer are not necessary. Apart from arranging a material layer 15, which in overlapping manner is formed into a single flexible container, a multitude of overlaps can be piled on top. of one another. A material layer 15 can be laid into a device suitable for such purpose in a manner that it overlaps several times. In order to effect a closing of the overlapping material layer 15 on the side, they are connected to one another in the lateral border region, in particular glued and/or welded. A cut is effected in transverse direction in order to obtain the opening of the flexible container and, in particular, in order to separate the overlapping layers from one another. This transverse cut can, for example, be effected with a knife, in which case a multitude of layers of material piled on top of one another can be cut simultaneously. A cutting device 18 is schematically shown as an example in Fig. 2. A welding head 19 is also schematically shown. The welding head 19 can enable, for example, thermal welding. The

welding head 19 can also effect area and/or spot welding. According to a preferred embodiment, one or several welding heads 19 are provided for ultrasonic welding. For this purpose the welding head 19 is designed as a sonotrode which, preferably, is connected to a generator, a converter and an amplitude transformer. According to one embodiment, ultrasonic welding is effected as far sound field welding. Another embodiment features it as near field welding. Within the framework of this invention far sound field welding is to be carried out when the sonotrode is at a distance of more than 6 mm from the welding area itself. The sonotrode is preferred to feature a structure 20. By means of structure 20 it is possible to direct the energy supply in a concentred and targeted manner resulting in a consistent and short welding process using little energy with reduced thermal damage to the nonwoven plastic, in particular the nonwoven fabric. It is also possible to hold the nonwoven fabric in the area to be welded in a manner that elevations result in the non- woven fabric in the form of structures. These can also serve as supply areas for the energy supply for ultrasonic welding. The structure preferably features ripples or grooves. The sonotrode 20 having such structure is preferably laid onto the nonwoven fabric in a form-fit manner. Energy is supplied subsequently and welding of the weld seams which lie on top of one another can be effected. In the case of a pile of stacked layers of material 15 which are altogether cut, or are also punched out for example, welding is preferably carried out so that the individual flexible containers can be separated subsequently. Cut- ting and punching out respectively of the layers of material can preferably be carried out in the same device in which welding, in particular ultrasonic welding, is also effected. For this purpose a short circuit cut-off of the ultrasound device is effected while the cutting tools and punching tools respectively are activated. During welding, preferably either time and/or energy are recorded and the welding process is adjusted on the basis of one or both monitored parameters.

Fig. 3 shows another example of an embodiment of a flexible container 1. This flexible container 1 comprises for example handle areas 21 which are integrated into the side walls 3, 4. Furthermore, a transverse weld seam 22 is shown. A fold 23 has the effect that the material of the flexible container 1 forms the bottom 7. An overlapping area region generated through fold 23 can, for example comprise side folds to the inside 24. In the stead of the folds to the inside 24, edges of cuts and of punches respectively can be provided. Along these edges the material is preferably glued and/or welded to side area 4. The transverse seam 22 can also be stabilized through this process. For further stabiliza- tion there can also be one or several welds and gluing areas 25 respectively between the folded area and side wall 4.

Fig. 4 shows as an exemplary embodiment a handle 8 which is preferably entirely made up of nonwoven fabric. The nonwoven fabric is smaller in a middle area 26. In an end area 27, by contrast, the handle becomes broader according to this example of an embodi- ment. This makes available in the end area 27 a larger area for tacking or welding or gluing it to a side wall of the flexible container.

Fig. 5 shows another embodiment of a handle 8 in cross section. A nonwoven web 28 features an additional reinforcement 29. This reinforcement 29 can, for example, be foam material. If the foam material features a special shape the nonwoven web 28 can thus be stabilized in its inherent form. Through the impact of force from the outside as it occurs in particular on gripping, this laminate can adjust to the respective palm of the person gripping and, at the same time, make available a sufficient area, which, in particular does not cut into balls of hands or similar skin parts of the hand.

The handles can be glued on, welded on or can be manufactured in any other way, also form-fit with, e.g., the remaining material layer. The handles can also been pattern bonded up to 100%.

Fig. 6 shows as a schematic view an exemplary embodiment of a device for manufacturing a flexible container 30. A material layer, in particular a layer of nonwoven fabric or a laminate with nonwoven is fed from an unwind 31 to a machine unit 32. A welding device 33, which according to this embodiment provides for ultrasonic welding, is preferably also integrated within the machine unit 32. In addition or as an alternative, a gluing unit 34 can also be included. Glue 35 can be sprayed on, swabbed on, applied as powder, glue strip, glue fiber or in any other way. the material can, for example, comprise a polymer which, when heated or activated, effects that the areas lying on stick to one another. As shown a multitude of flexible containers can be manufactured at the same time. It is possible to arrange carrying means in CD direction and MD direction respectively. As an example, first carrying means 36.1 in MD direction and second carrying means 36.2 in CD direction are shown in a broken line. A sonotrode 37 is preferably of such design that at least a longitudinal side of the future flexible container can be welded. It is, however, also possible to provide for pattern welding across the width of an area in the stead of line welding or lengthwise welding. For example, certain fusion patterns can thus be generated at the surface. A lengthwise weld preferably has a width of at least 1 mm to preferably 20 mm. If a welding pattern is used, it is preferred that at least 30 %, preferably up to 70 %, of the

areas to be bonded are melted together. It is also possible to combine the lengthwise weld with a pattern weld. Welding by means of ultrasound can be continuous or intermittent welding can be provided for. In particular, for fastening handles to the future flexible container, intermittent welding is to be employed. For instance, different bonding patterns can be generated by welding whereby a direction of the forces to be absorbed in the welding area can be adjusted in a targeted manner in the material layer. Welding is to be carried out, preferably at least in the area of the handles, in a way that it affects between 90 % to 100 % of the adjacent areas. If a bottom is to be welded in, for example a bottom insert, welding is preferably also intermittent. Here, it is preferably made use of the fact that in intermittent welding, in particular in the case of spot welding, a defined supply of ultrasound energy is possible. This allows the welding together of several layers which are piled on top of another. Contours and shapes can also be precisely brought in.

It has proved to be an advantage if a polypropylene is used as basic material for manufac- turing the nonwoven fabric used. The polypropylene material preferably features a MFI in the range of 10 to 30 g/10min, preferably in an area between 15 to 20 g/10min. Also higher MFI's can be used. If the polypropylene is used together with polyethylene, the latter preferably has the same MFI range. The polypropylene as well as the polyethylene can be in a blend. At least a third polymer can preferably be used here in addition. It is also possible to use an elastic polymer material for manufacturing the nonwoven fabrics. For example, a thermoplastic polyurethane (TPU) or an elastic polypropylene (ePP) or other thermoplastic elastomers (TPE) can be used. An elastic nonwoven fabric can also be manufactured by adding suitable additives. It is, for example, possible to use a DAPP for this purpose. In this respect reference is made, for instance, to the relevant disclosure in US 5,804,286.

In one embodiment, the multipolymer fibers may comprise from 1 to 50 percent by weight polyethylene and from 99 to 50 percent by weight polypropylene. Fabrics formed from such blends exhibit low fuzz and good elongation.

In applications where tensile strength is particularly important and high elasticity is of lesser concern, the composite fabric may include a coherent, extensible nonwoven web formed of fibers of a polyethylene and polypropylene blend where the polyethylene is present in the range of 1 % to 10 % by weight and the polypropylene is present in the range of 90 % to 99 % by weight. In still another embodiment, very substantial and surprising increases in elongation can be achieved by blending a third polymer component into the

blend. For example, the multipolymer fibers may include a dominant amount of a polypropylene, such as isotactic polypropylene, a small amount of a polymer having low mutual affinity with the dominant polymer, such as polyethylene, and an additional third polymer which either reduces crystallinity and/or compatibilizes the blend. What results is a softer web, with extremely high extensibility. Preferred multipolymer fibers according to this embodiment may comprise greater than 50 % by weight polypropylene, 1 to 10 percent polyethylene, and 10 to 40 percent of the third polymer. Suitable additional third polymers include polypropylene copolymers and terpolymers such as the commercially available Catalloy™ copolymers available from Montell. These resins are characterized by having the comonomer(s) exist to some degree in blocks, and wherein at least some portion of the polymer chain is miscible with one or the other, or both, dominant and dispersed polymer phases. Other suitable polymers are the Reflex™ flexible polyolefins from Rex- ene. These crystallinity-reducing resins are characterized as having atactic segments present in the polymer chain, such that the "tacticity" of the polymer is affected.

Especially preferred multipolymer fibers according to this embodiment comprise 65 to 80 percent isotactic polypropylene, 1 to 5 percent polyethylene, and 15 to 30 percent of a polyolefin copolymer wherein at least a portion of the chain is miscible with isotactic polypropylene.

Another class of useful and advantageous products according to this aspect of the invention employ multipolymer fibers formed of a polymer blend comprising a soft, extensible poylmer phase, and at least one additional polymer having low mutual affinity with the soft, extensible phase, such that it modifies either the rheological, mechanical, and/or thermal properties of the fibers in a way that improves processability (e.g. melt spinning), bonding, and/or abrasion resistance while maintaining high extensibility. In a preferred embodiment the soft, extensible phase is present as a dominant, continuous phase. For example, polyethylene can be used as the soft, extensible dominant phase and a polypropylene as the additional modifying polymer. In a preferred embodiment the additional polymer is added in a small proportion relative to the dominant phase. In another preferred embodiment, the additional polymer exhibits higher viscosity relative to the dominant phase. Blending a relatively small proportion of the higher viscosity polypropylene with the soft, extensible polyethylene imparts greatly increased abrasion resistance to a nonwoven fabric formed from the polymer blend, without significant adverse effect upon other important fabric properties, such as extensibility, softness, tensile strength, etc. The spinnability of the polyethylene is also improved by the presence of the additional poly-

propylene. According to this embodiment, the fibers preferably comprise between 2 to 50 percent by weight of the propylene polymer, e.g. 3 % ethylene-propylene copolymer, and 98 to 50 percent by weight of the soft, extensible polymer, e.g. polyethylene. In one particularly preferred embodiment, the fiber composition may range from 5 to 40 percent by weight propylene polymer, and most desirably between 5 to 25 percent by weight propylene polymer and 75 to 95 percent by weight polyethylene. Especially suited for applications requiring good extensibility, tensile strength and abrasion resistance are fiber compositions of from 5 to 25 percent by weight propylene polymer. A most preferred embodiment contains 5 to 25 percent by weight of ethylene-propylene copolymer or terpolymer and 75 to 95 percent by weight linear low density polyethylene. In these embodiments, the lower melting polyethylene is present as a substantially continous phase in the blend and the higher melting propylene polymer is present as a discontinous phase dispersed in the polyethylene phase.

In producing the fibers, the polyethylene and polypropylene components are combined in appropriate proportional amounts and intimately blended before being melt-spun. In some cases sufficient mixing of the polymer components may be achieved in the extruder as the polymers are converted to the molten state. In other cases, more dynamic mixing may be required.

Various types of polyethylene may be employed. As an example, a branched (i.e., nonlinear) low density polyethylene or a linear low density polyethylene (LLDPE) can be utilized and produced from any of the well known processes, including metallocene and Ziegler-Natta catalyst systems. LLDPE is typically produced by a catalytic solution or fluid bed process under conditions established in the art. The resulting polymers are characterized by an essentially linear backbone. Density is controlled by the level of comonomer incorporated into the otherwise linear polymer backbone. Various alpha-olefins are typically copolymerized with ethylene in producing LLDPE. The alpha-olefins which preferably have four to eight carbon atoms, are present in the polymer in an amount up to about 10 percent by weight. The most typical comonomers are butene, hexene, 4-methyl-1- pentene, and octene. In general, LLDPE can be produced such that various density and melt index properties are obtained which make the polymer well suited for melt-spinning with polypropylene. In particular, preferred density values range from 0.87 to 0.95 g/cc (ASTM D-792) and meld index values usually range from 0.1 to about 150 g/10 min. (ASTM D1238-89, 190 ⁰ C). Preferably, the LLDPE should have a melt index of greater than 10, and more preferably 15 or greater for spunbonded filaments. Particularly pre-

ferred are LLDPE polymers having a density of 0.90 to 0.945 g/cc and a melt index of greater than 25. Examples of suitable commercially available linear low density polyethylene polymers include those available from Dow Chemical Company, such as ASPUN Type 6811 (27 Ml, density 0.923), Dow LLDPE 2500 (55 Ml, 0.923 density), Dow LLDPE Type 6808 A (36 Ml, 0.940 density), and the Exact series of linear low density polyethylene polymers from Exxon Chemical Company, such as Exact 2003 (31 Ml, density 0.921).

Various polypropylenes made by processes known to the skilled artisan may also be employed. In general, the polypropylene component can be an isotactic or syndiotactic pro- pylene homopolymer, copolymer, or terpolymer. Examples of commercially available propylene homopolymers which can be used in the present invention include SOLTEX Type 3907 (35 MFR; CR grade), HIMONT Grade X10054-12-1 (65 MFR), Exxon Type 3445 (35 MFR), Exxon Type 3635 (35 MFR), AMOCO Type 10-7956F (35 MFR), and Aristech CP 350 J (melt flow rate approximately 35). Examples of commercially available copolymers of propylene include Exxon 9355 which is a random propylene copolymer with 3 % ethylene, 35 melt flow rate; Rexene 13S10A, a 10 melt flow rate random propylene copolymer with 3% ethylene; Fina 7525MZ, an 11 melt flow rate 3% ethylene random propylene copolymer, Montel EPIX 3OF, an 1.7% ethylene, 8 melt flow rate random copolymer of propylene. When the propylene polymer is the dominant continuous phase of the blend, the preferred melt flow rate is greater than 20. When the propylene polymer exists as the dispersed phase of the blend, the preferred melt flow rate is less than 15 and most preferably less than 10.

In still another embodiment, the multipolymer fibers of the web may be bicomponent or multicomponent fibers or filaments. The term bicomponent or multicomponent refers to the existence of the polymer phases in discrete structured domains, as opposed to blends where the domains tend to be dispersed, random or unstructured. The polymer components can be configured into any number of configurations including sheath-core, side-by- side, segmented pie, islands-in-the-sea, or tipped multilobal. A coherent extensible nowoven web can be made, for example, from a sheath-core bicomponent fiber having a polyester core and a polyethylene sheath, or the sheath or core can comprise a blend as discussed above. Alternatively, the extensible web can comprise a single web containing a combination of spunbonded filament and meltblown fibers or a combination of carded staple fibers and meltblown fibers.

Prior to being manufactured into a flexible container the nonwoven fabric can be pre- stretched thus, for instance, increasing the tensile strength of the nonwoven fabric. According to one embodiment, a stretch of at least 20 % in each case, preferably at least 30 % in each case, in CD and/or MD direction is carried out. Another embodiment provides for a stretch ratio to be 2 to 1 , in particular up to 3 to 1 in CD and/or MD direction.

Fig. 7 shows a schematic view of a possible print station 38. The material layer can, for instance, feature a basic shade through pigmentation prior to being processed into a flexible container. Also, in the case of laminates there can be different pigmentations and thus colorations. Thus, an inside of a flexible container can feature a different colour than an outside of the flexible container. In addition, it is possible to apply a print to the surface of the material. The surface can be a film or a nonwoven fabric surface. Multi-colour printing is preferably used for applying prints. A flexo-five-colour-print is preferably used whereby a printing plate is employed equipped with up to 42 grids, in particular in a range up to 32 grids. The print colours are preferably water-based. It is, however, also possible to use print colours made up on the basis of a solvent. It is also possible to carry out a printing process by ink jet printing. Other ways to effect printing are also possible. Where necessary, the surface can be pre-printed, for instance with a first coat before the figurative element itself is printed on. In addition, as well as in the stead of printing, relief-like struc- tures can also be generated at the surface. Printing as well as generating the relief-like structure can be effected on one side or on both sides. The flexible container can also feature different figurative elements on both sides. It is also possible that the surface of the flexible container is painted. In the case of printing on the surface of the flexible container it is preferred that the nonwoven material used features embossing on the surface ranging in an area of at least 20 % of the total area of the nonwoven fabric used. The nonwoven fabric preferably features embossing larger than 25%. An improved adherence of the print colour to the flat embossed areas of the nonwoven layer can thus be effected.