JPWO2021018526A5 - - Google Patents

Description

The invention relates to an apparatus for the production of a nonwoven material having at least one nonwoven web, in which at least one spinning device or at least one spinning beam for spinning out fibers is provided, in which a depositing conveyor, in particular a depositing screen belt, is provided, on which the fibers can be deposited to form a nonwoven web. The invention likewise relates to a method for producing a corresponding nonwoven material.
In the context of the present invention, fibers made of thermoplastic synthetic materials are used as fibers, and preferably endless filaments made of thermoplastic synthetic materials, which differ from staple fibers by their, so to speak, endless length, which has a much shorter length, for example between 10 mm and 60 mm.
The endless filaments used within the scope of the present invention are in particular endless filaments made of a preferably thermoplastic synthetic material, produced in a spunbonding apparatus or by a spunbonding process.

Devices and methods of the type described at the outset are known in various embodiments from practice, and thus it is known to deposit endless filaments onto a depositing conveyor into a nonwoven web, to subject this nonwoven web to a presolidification, and subsequently to carrying out a final solidification of this nonwoven web.
Preconsolidation is carried out, for example, by means of compression rolls, and final consolidation is carried out, in particular, in a hot air oven (through air bonding). Furthermore, it is likewise known for air or process air to be sucked through the depositing screen belt in the region of the deposition of the fibers on the depositing screen belt. Preconsolidation and final consolidation are carried out on the same depositing conveyor or on the same depositing screen belt in many known devices.
The invention is based on the recognition that it is not always advantageous to carry out all solidification procedures on the same depositing conveyor.

For certain applications, so-called high-loft products are highly advantageous, which are nonwoven webs or spunbonded nonwovens having a relatively high thickness and high softness.
The production of this high loft product with the desired properties is not always easy, since the nonwoven material also needs to be solidified, which causes a disturbance in thickness and/or softness. From that situation, there is now a conflict of goals of high softness and thickness of the nonwoven material on the one hand, and sufficient strength or abrasion resistance on the other hand.
Previously known devices and methods often did not provide any satisfactory results in this respect.

Published publication: "Automatic Crimp Measurement on Staple Fibres" Denkendorf Colloquium, "Textile Mess- und Prüftechnik", 9.11.99, Dr. Ulrich Moerschel (especially page 4, FIG. 4).

In view of the above, the technical problem underlying the present invention is to provide an apparatus of the type described at the outset, by means of which advantageous pre-solidification, and likewise optimal final solidification, of nonwoven materials can be achieved, and by means of which, in addition, nonwoven materials of likewise great thickness and high flexibility can be produced without any problems, if required.
Furthermore, the technical problem underlying the present invention is to provide a method for producing such a nonwoven material.

To solve this technical problem, the present invention provides:
1. An apparatus for the production of a nonwoven material having at least one nonwoven web, comprising:
At least one spinning device or at least one spinning beam is provided for spinning out fibers, with a depositing conveyor, in particular a depositing screen belt, being provided on which the fibers can be deposited to form a nonwoven web,
At least one hot air pre-solidification device is provided for hot air pre-solidification of the nonwoven web on the depositing conveyor or on the depositing screen belt,
in which, in the transport direction of the nonwoven web, a further conveyor, in particular in the form of a transport belt, is arranged behind the depositing conveyor or depositing screen belt for receiving the pre-consolidated nonwoven web from the depositing conveyor, and at least one final consolidation device, in particular at least one hot air final consolidation device, is provided for final consolidation or hot air final consolidation of the nonwoven web on the further conveyor or on the transport belt, and
In this case, the hot air pre-solidification of the nonwoven web is performed on the depositing conveyor or the depositing screen belt.
the nonwoven web has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, before being transferred to the further conveyor or the transfer belt;
This is possible under the condition that
It teaches that.
Machine direction (MD) means within the scope of the present invention in particular the transport direction of a depositing conveyor or of a nonwoven web.

It is possible for the nonwoven material produced according to the invention to have just one nonwoven web or layer, or it is equally possible for the nonwoven material to have several nonwoven webs or layers arranged one on top of the other that are combined into a nonwoven laminate.
When several nonwoven webs are arranged one on top of the other, each nonwoven web is expediently provided with one spinning device or one spinning beam associated therewith. The number of spinning devices or spinning beams arranged one behind the other usually corresponds to the number of nonwoven webs or nonwoven layers that are to be combined on top of each other into the nonwoven laminate.

The depositing conveyor or depositing screen belt is in particular designed as an endlessly circulating depositing screen belt. Expediently, the conveyor or transport belt is designed as an endlessly circulating transport belt. It is within the scope of the invention if the depositing conveyor or depositing screen belt is designed as ventilated for the through-suction of process air. In principle, it is within the scope of the invention if further conveyors or transport belts are designed as ventilated.
In principle, it is also possible for the further conveyor to otherwise likewise be configured as a roll or drum or the like.

According to the invention, separate conveyors are used for the pre-solidification of the nonwoven web on the one hand and for the final solidification of the nonwoven web on the other hand, namely a depositing conveyor or depositing screen belt for the hot air pre-solidification and a further conveyor or transport belt for the final solidification or hot air final solidification.
The invention is therefore based on the realization that the separation of the conveyors for pre-solidification on the one hand and for final solidification on the other hand is unexpectedly particularly advantageous for the nonwoven material to be produced and, in particular, also induces advantages in the processing of the method for producing the nonwoven material, in particular for nonwoven materials with lower areal weights and/or for the production of nonwoven materials at higher production speeds.

The invention is based in particular on the recognition that the device according to the invention and the method implemented by the device according to the invention are particularly advantageous from an energy point of view, since in those installations known from the prior art in which pre-consolidation and final consolidation take place on the same depositing screen belt, relatively high energy losses inevitably occur.
In the hot air final solidification device, the nonwoven material or the screen belt is heated to a relatively high temperature. The endlessly circulating depositing screen belt is subsequently guided again through a depositing area for the fibers, in which process air is sucked through the depositing screen belt and which is thus cooled relatively clearly.
This cooled screen belt subsequently needs to be heated again in an energetically expensive manner in a final solidification device, which involves significant energy losses, which increase even more with higher product velocities - for example in multi-beam installations - and which are advantageously avoided within the scope of the teaching according to the invention.

The device according to the invention is likewise particularly well suited for the production of high loft products, by means of which it is possible to achieve an optimum compromise between sufficient thickness and high softness of the nonwoven material, and in addition a satisfactory strength of this material.
The invention is based on the realization that the nonwoven material after presolidification should have a strength in the machine direction (MD) within the interval claimed according to the invention. As a result, a voluminous and soft nonwoven material with optimal strength can be achieved.

In particular, the teachings according to the invention or the apparatus according to the invention prove useful in nonwoven laminates consisting of at least two nonwoven webs or more than two nonwoven webs, where the nonwoven laminates are produced by a two-beam or multiple-beam system.

According to a particularly advantageous embodiment of the invention,
the nonwoven material is a nonwoven laminate consisting of at least two nonwoven webs, in which at least two spinning devices or spinning beams are provided for producing fibers for the nonwoven webs,
In this case, a first spinning device or a first spinning beam is provided for spinning out a first fiber, and the first fiber can be deposited on the depositing conveyor or the depositing screen belt into a first nonwoven web,
In this case, a second spinning device or a second spinning beam is provided for spinning out a second fiber, the second spinning beam being downstream of the first spinning beam in the conveying direction of the depositing conveyor, and the second fiber can be deposited onto a second nonwoven web on the depositing conveyor or on the first nonwoven web,
At least one hot air pre-solidification device is provided between the first spinning beam and the second spinning beam as at least one first hot air pre-solidification device for the hot air pre-solidification of the first nonwoven web,
In this case, at least one second hot-air pre-consolidation device for the hot-air pre-consolidation of the second nonwoven web or of the laminate consisting of the first and second nonwoven webs is arranged behind the second spinning beam in the conveying direction of the fiber deposit, and the laminate can be or is transferred from the depositing conveyor to the further conveyor, in particular in the form of a transport belt,
The laminate is then final solidified on the further conveyor by the final solidification device, in particular the hot air final solidification device, and
The hot air pre-solidification of the nonwoven web or laminate on the depositing conveyor comprises:
the laminate has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, prior to delivery to the further conveyor;
This can be done under certain conditions.

If within the scope of the present invention two or more spinning devices or spinning beams are used and two or more nonwoven webs are produced for the nonwoven laminate according to the present invention, it is within the scope of the present invention that each spinning device or each spinning beam is downstream connected with at least one hot air pre-solidification device for hot air pre-solidification of the nonwoven web or of the nonwoven web aggregate.
It is further within the scope of the present invention that the deposition of fibers for the individual nonwoven webs and the hot air pre-consolidation are carried out on the same depositing conveyor or depositing screen belt, with final consolidation subsequently taking place on yet another conveyor or transport belt.
Basically, it is within the scope of the invention that in the production of only one nonwoven web or in the production of several nonwoven webs by several spinning beams , at least one intermediate conveyor or intermediate transport belt is interposed between the depositing conveyor and the further conveyor. In this case, the teaching according to the invention is to be understood advantageously in such a way that the individual nonwoven webs or nonwoven web aggregates have their strength in the machine direction (MD) within the intervals claimed according to the invention before being transferred onto the at least one intermediate conveyor. This intermediate conveyor can otherwise also be a roll or a deflection roll, a roller, a drum or the like.

It is within the scope of the present invention that at least one spinning unit or at least one spinning beam of the apparatus according to the present invention or the apparatus components belonging to at least one spinning unit or at least one spinning beam of the apparatus according to the present invention are configured as spunbonding units for producing spunbonded nonwoven materials made of endless filaments. According to an embodiment of the present invention, all spinning units or spinning beams and therefore the corresponding apparatus components are each configured as spunbonding units for producing spunbonded nonwoven webs with endless filaments.

A very particularly advantageous embodiment of the invention is characterized in that at least one of the spinning devices or at least one of the spinning beams is
According to a preferred embodiment of the invention, all spinning devices or all spinning beams of the device according to the invention are configured for the production of bicomponent/multicomponent fibers, in particular bicomponent/multicomponent filaments.
It is further within the scope of the present invention that the device is configured for producing at least one nonwoven material or at least one nonwoven web from crimped fibers or crimped endless filaments. Advantageously, at least one of the spinning devices or at least one of the spinning beams is configured for the production of crimped fibers or crimped endless filaments.
When using multiple spinning beams for the device according to the invention, at least one spinning beam or at least two spinning beams or all spinning beams are configured for producing crimped fibers or crimped endless filaments.

Of particular importance are embodiments of the device according to the invention or of the method according to the invention for the production of at least one nonwoven web consisting of crimped fibers or crimped endless filaments.
In this way, high loft products can be produced very easily, with the invention being based on the realization that the advantageous properties of such high loft products can be unexpectedly maintained on the basis of the structure of the apparatus according to the invention or on the basis of the implementation of the method according to the invention, and that nevertheless, effective processing of the nonwoven web or of these nonwoven webs with sufficient strength is possible.
For the production of crimped fibers or crimped endless filaments, fibers or filaments with an eccentric core-sheath configuration (Kern-Mantel configuration) or a side-by-side configuration (Seite-an-Seite configuration) can be used within the scope of the present invention, with fibers or filaments with an eccentric core-sheath configuration being treated with advantage. The latter fibers have proven to be particularly useful for the device according to the invention or the method according to the invention.
A highly advantageous embodiment of the endless filament with an eccentric core-sheath construction used within the scope of the present invention is explained in more detail further below.

A particularly expedient embodiment of the present invention provides for the fibers or filaments spun by at least one spinning beam :
at least one cooling device for cooling said fibers;
The cooling device is followed by at least one drawing device for drawing the fibers, which is preferably connected to at least one diffuser in the flow direction of the fibers/filaments.
A highly preferred embodiment of the present invention is characterized in that the mechanical unit consisting of the cooling device and the stretching device is formed as a closed mechanical unit, and
It is characterized in that no additional air can be fed from the outside into this mechanical unit, except for the supply of cooling air in the cooling device. Expediently, the fibers/filaments leaving the diffuser are directly deposited on a deposition conveyor or a deposition screen belt.

An embodiment of the invention that has proven to be particularly useful is characterized in that the or one hot air preconsolidation device is made in the form of at least one hot air knife and/or in the form of at least one hot air oven.
If two or more spinning beams are used within the scope of the device according to the invention, the first hot air pre-solidification device between the first and second spinning beams is preferably designed in the form of at least one first hot air knife and/or in the form of at least one first hot air oven. Expediently, the second hot air pre-solidification device behind the second spinning beam is designed in the form of at least one second hot air knife and/or in the form of at least one second hot air oven.

A proven embodiment of the invention is characterized in that the device element with a spinning beam is followed firstly by at least one hot air knife and that this hot air knife is followed by at least one hot air oven, whereby an embodiment of the invention is characterized in that only one hot air knife is followed by the spinning beam and that this hot air knife is followed by, on the other hand, only one hot air oven.

In the case of a plurality of spinning units or spinning beams in the scope of the device according to the invention, it is preferred that first of all at least one first hot air knife is downstream of the first spinning beam in the conveying direction of the first nonwoven web, and
This first hot air knife is followed downstream by at least one first hot air oven upstream of the second spinning beam .
Furthermore, it is expedient if, in the transport direction of the laminate, at least one second hot air knife is connected downstream of the second spinning beam , and
This first hot air knife is in turn followed by at least one second hot air oven.
It is within the scope of the present invention for the nonwoven web or nonwoven web laminate to leave the hot air oven as a final hot air pre-consolidation device before delivery to yet another conveyor or transport belt.

Basically, other combinations of hot air pre-solidification devices are also possible within the scope of the invention, so that it is also possible for only one hot air knife to be connected downstream as hot air pre-solidification device to one spinning beam or, in the case of a two-beam or multi-beam installation, to at least one spinning beam .
According to one embodiment, a hot air knife is downstream of a first spinning beam , which in turn is downstream of a hot air oven for pre-solidification. A single hot air knife is downstream of the second beam, in this embodiment, as a hot air pre-solidification device.
Another embodiment is characterized in that only one hot air knife is downstream of the first spinning beam as a hot air pre-solidification device, and that one hot air knife is downstream of the second spinning beam and that a hot air oven is also downstream of this hot air knife as a hot air pre-solidification device.
According to another embodiment variant, it is also possible that just one hot air oven is arranged as hot air pre-solidification device behind each spinning beam.Therefore , within the scope of the present invention, there are different variants for the combination of hot air pre-solidification devices.

A preferred embodiment of the present invention is characterized in that the hot air knife exposes the nonwoven web or the laminate to hot air over a width area in the machine direction (MD) of 15 to 300 mm, in particular 30 to 250 mm, advantageously 40 to 200 mm and preferably 40 to 150 mm. Expediently, the distance of at least one hot air nozzle of the hot air knife to the surface of the depositing conveyor or the surface of the depositing screen belt is 2 to 200 mm, in particular 3 to 100 mm.
Expediently, the width and spacing regions mentioned above also apply in the case of a multi-beam installation to the respective hot air knife used for the hot air presolidification device.

Furthermore, a proven useful embodiment of the invention is characterized in that the hot air oven exposes the nonwoven web or the laminate to hot air over a width area in the machine direction (MD) of 280 mm to 2,000 mm, in particular 290 mm to 1,800 mm and preferably 300 mm to 1,500 mm.Preferably, the hot air outlet openings of the hot air oven have a distance of 12 mm to 200 mm, in particular 20 mm to 150 mm and preferably 25 mm to 120 mm, relative to the surface of the depositing conveyor or the surface of the depositing screen belt.
Expediently, the width and/or spacing regions mentioned above also apply in the case of a multi-beam installation to each hot air knife used for hot air preconsolidation.

It is within the scope of the invention that a cooling zone is arranged behind the or each hot air knife and/or behind the or each hot air oven, in which the nonwoven web is stabilized by cooling. Expediently, such a cooling zone has a length of, for example, 400 mm to 600 mm and is passed through by cooling air with a speed of, for example, 1 to 2 m/s. As a result, the stacking conveyor is cooled as well as the nonwoven web.

A particularly advantageous embodiment that is of special importance within the scope of the present invention is characterized in that the temperature of the surface of the further conveyor or transport belt is higher than the temperature of the surface of the depositing conveyor or depositing screen belt in the transfer area of the nonwoven web or laminate to this further conveyor or transport belt upstream of the hot air preconsolidation device in the conveying direction.
If, according to a variant of the embodiment of the invention, at least one intermediate conveyor is arranged between the depositing conveyor and the further conveyor, this embodiment means in particular that the temperature of the surface of the further conveyor, in particular the transport belt, is higher in the conveying direction than the temperature of the surface of the depositing conveyor or the depositing screen belt in the handover area of the nonwoven web or the laminate to the intermediate conveyor before the hot air final solidification device and/or higher than the temperature of the surface of this intermediate conveyor.
Expediently, in these embodiments, the surface temperature of the further conveyor or transport belt is at least 5° C., preferably at least 10° C., and preferably at least 15° C., and very preferably at least 20° C., higher than the surface temperature of the stacking conveyor and/or intermediate conveyor.
If, within the scope of the present invention, an intermediate conveyor having only a transport function is used, the surface temperature of this intermediate conveyor is expediently lower than the surface temperature of the further conveyor and, advantageously, the surface temperature of this intermediate conveyor is likewise lower than the temperature of the nonwoven web or laminate when it enters the intermediate conveyor.

In order to solve this technical problem, the present invention further comprises:
1. A method for producing a nonwoven material having at least one nonwoven web, comprising the steps of:
In this case, fibers are spun and deposited onto the nonwoven web on a depositing conveyor, in particular a depositing screen belt,
The nonwoven fabric is presolidified on the depositing conveyor by hot air, and the nonwoven fabric web is then transferred from the depositing conveyor or the depositing screen belt to a further conveyor or transfer belt, and
In this case, the hot air presolidification is
the nonwoven web has a strength in the machine direction (MD) of from 0.5 to 5 N/5 cm, in particular from 0.7 to 3.5 N/5 cm, and preferably from 0.8 to 3.5 N/5 cm, before being transferred to the further conveyor;
This is carried out under the condition that
It teaches that.

A particularly advantageous embodiment of the method according to the invention is characterized in that the nonwoven laminate is produced from at least two nonwoven webs, in particular at least one of the nonwoven webs having crimped fibers, in which a first fiber is spun and deposited on a depositing conveyor, in particular a depositing screen belt, onto the first nonwoven web,
In the process, second fibers are spun and these second fibers are deposited on the first nonwoven web transported on a depositing conveyor onto a second nonwoven web or onto the laminate consisting of both nonwoven webs,
In this case, after the deposition of the first fibers and before the deposition of the second fibers, the first nonwoven web is pre-solidified by hot air, and in this case, after the deposition of the second fibers, the second nonwoven web or the laminate consisting of the first nonwoven web and the second nonwoven web is pre-solidified by hot air,
The laminate is then transferred from the depositing conveyor or depositing screen belt to the further conveyor or transfer belt, and the hot air pre-solidification is then
the laminate has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, prior to delivery to the further conveyor;
It is characterised by the fact that it is carried out under certain conditions.

A particularly useful embodiment of the method according to the invention is characterized in that the fibers - in particular the fibers of the first spinning beam and/or the fibers of the second spinning beam - are spun as spunbond filaments or endless filaments, in particular as bicomponent or multicomponent filaments, and
It is preferably characterized in that it is deposited as crimped filaments, in particular onto the first nonwoven web and/or onto the second nonwoven web.
According to a particularly advantageous embodiment of the invention, the fibers - in particular the fibers of the first spinning beam and/or the fibers of the second spinning beam - are spun as bicomponent or multicomponent filaments with an eccentric core-sheath structure.

In particular, within the scope of the present invention, preference is given to bicomponent or multicomponent filaments with an eccentric core-sheath structure, in which the sheath has a constant or essentially constant thickness d in the filament cross section over at least 20%, in particular over at least 25%, advantageously over at least 30%, preferably over at least 35%, and very advantageously over at least 40% and particularly advantageously over at least 45% of the filament circumference.
It is particularly advantageous within the scope of the present invention for the sheath of the filaments to have a constant or essentially constant thickness d over at least 50%, preferably over at least 55%, and more preferably over at least 60% of the filament circumference. Expediently, in these filaments, the inner core occupies more than 50%, in particular more than 55%, preferably more than 60%, and more preferably more than 65% of the area of the filament cross section of these filaments.
Preferably, the inner core of the filaments is formed in the shape of a segment of a circle, viewed in the cross section of the filament, and has, with respect to its outer periphery, a circular arc-shaped or essentially circular arc-shaped outer periphery as well as a straight or essentially straight outer periphery.Furthermore, it is advantageous for the sheath of the filaments to be formed in the shape of a segment of a circle outside the sheath region having a constant thickness d, viewed in the cross section of the filament, and the segment of a circle has, with respect to its outer periphery, a circular arc-shaped or essentially circular arc-shaped outer periphery as well as a straight or essentially straight outer periphery.
According to a highly preferred embodiment, the thickness of the sheath of these preferred filaments, within the region of constant or essentially constant thickness d of this sheath, is less than 10%, in particular less than 8%, preferably less than 7% of the filament diameter D or the maximum filament diameter D. Furthermore, it is within the scope of the invention that in these preferred filaments, the distance a from the surface center of gravity of the sheath to the surface center of gravity of the inner core, in relation to the filament cross-section, is from 5% to 45%, in particular from 6% to 40%, and preferably from 6% to 36% of the filament diameter D or the maximum filament diameter D.

A particularly preferred embodiment of the present invention is characterized in that the fibers or filaments produced according to the invention consist or consist essentially of at least one polyolefin. If bicomponent or multicomponent filaments are produced within the scope of the present invention, advantageously bicomponent or multicomponent filaments are the key element, in which at least one component or both or all components consist or consist essentially of at least one polyolefin.
In the production of filaments with an eccentric core-sheath structure, preferably at least the sheath consists of at least one polyolefin or essentially of at least one polyolefin. According to an embodiment that has proven to be very useful, the sheath consists of polyethylene or essentially of polyethylene, and preferably the core consists of polypropylene or essentially of polypropylene.
According to another preferred embodiment, the inner core consists or essentially consists of at least one polyester and the outer jacket consists or essentially consists of at least one polyolefin. As polyester, preferably polyethylene terephthalate (PET) is used within the scope of the present invention.
In a preferred embodiment, the inner core consists or essentially consists of PET and the outer jacket consists or essentially consists of polyethylene. Yet another embodiment is characterized in that the inner core consists or essentially consists of at least one polyester and the outer jacket consists or essentially consists of at least one copolyester.
It is within the scope of the invention that the synthetic material components of the sheath have a lower melting point than the synthetic material components of the core. Within the scope of the invention, fibers or filaments made of the above-mentioned synthetic materials have proven to be very particularly useful. In particular, bicomponent or multicomponent filaments with an eccentric core-sheath structure have proven to be useful, the sheath of which consists or essentially consists of polyethylene and the core of which consists or essentially consists of polypropylene.

An embodiment of the invention that has proven to be extremely useful is one in which the filament component has an eccentric core-sheath configuration, or the core and/or the jacket of the filament is:
They are characterized in that they consist or essentially consist of at least one polymer from the group: "polyethylene, polyolefin copolymers, in particular polyethylene, polypropylene, polyethylene copolymers, polypropylene copolymers; polyesters, polyester copolymers, in particular polyethylene terephthalate (PET), PET copolymers, polybutylene terephthalate (PBT), PBT copolymers, polylactic acid, polylactic acid copolymers".
It is likewise within the scope of the present invention that mixtures or blends of the aforementioned polymers may be used for the components or for the core and/or jacket. Furthermore, it is within the scope of the present invention that in endless filaments having an eccentric core-jacket structure, the synthetic material in the jacket has a lower melting temperature than the synthetic material in the core.

Advantageously, in the case of the production of nonwoven materials or one-layer nonwoven material products, the hot air pre-solidification of the nonwoven web is carried out at hot air temperatures of 80°C to 200°C, in particular 100°C to 175°C, preferably 110°C to 150°C and very preferably 115°C to 140°C, respectively. It is furthermore recommended that the hot air has a speed of 1.9 to 6 m/s, in particular 2 to 5 m/s and preferably 2.2 to 4.5 m/s during the hot air pre-solidification by the hot air knife.

A particularly preferred embodiment of the method according to the invention is characterized in that the at least one produced nonwoven web, in particular the first nonwoven web and/or the laminate consisting of the first nonwoven web and the second nonwoven web,
It is characterised by being pre-consolidated with hot air, first by means of a hot air knife and subsequently by means of a hot air oven.
The hot air preconsolidation is carried out by means of a hot air knife at a hot air temperature of from 80° C. to 200° C., in particular from 100° C. to 180° C., and preferably from 120° C. to 170° C., and very preferably from 120° C. to 160° C. Furthermore, the hot air has a speed of from 1.9 to 6 m/s, in particular from 2 to 5.5 m/s, and preferably from 2.2 to 4.4 m/s, during the hot air preconsolidation by means of the hot air knife.

If the hot air pre-solidification of the nonwoven web or nonwoven web laminate is carried out according to one embodiment by just one pre-solidification mechanism unit, in particular just one hot air knife, the hot air temperature is carried out at a hot air temperature in the range from 80°C to 250°C, in particular from 110°C to 200°C, and preferably from 120°C to 190°C and very preferably from 130°C to 180°C.
It is furthermore recommended that the hot air during hot air preconsolidation by means of the hot air knife has a speed of 1.9 to 8 m/s, in particular 2 to 5.5 m/s and preferably 2.2 to 5.5 m/s.

the nonwoven webs, in particular the first nonwoven web and/or the laminate consisting of the first nonwoven web and the second nonwoven web, are pre-solidified by hot air using at least one hot air oven, and
It is within the scope of the invention that the hot-air preconsolidation is carried out with hot air at a temperature of from 110°C to 180°C, in particular from 115°C to 170°C and preferably from 120°C to 160°C.
As a recommendation, the hot air has a velocity of from 1 to 2.5 m/s, in particular from 1.1 to 1.9 m/s and preferably from 1.2 to 1.8 m/s, during this hot-air preconsolidation in a hot-air oven.

It is further within the scope of the present invention that the nonwoven web or nonwoven laminate is finally solidified after the transfer from the stacking conveyor to another conveyor or transport belt. It has proven useful to carry out the final solidification as hot air final solidification. Expediently, the hot air final solidification is carried out in a hot air oven and/or a drum oven and/or a double belt oven and/or a parallel thermobonder.
A preferred embodiment is characterized in that the final consolidation is carried out by through air bonding in a hot air oven. It is further within the scope of the present invention that the final consolidation may be a combination of hot air final consolidation and electromagnetic heating (e.g. infrared-high frequency heating or microwave-high frequency heating) of the nonwoven material or nonwoven laminate.
The temperature of the hot air is expediently greater than 100° C., preferably greater than 110° C. The speed of the hot air during this final solidification has proven to be advantageously greater than 1 m/s, preferably greater than 1.1 m/s.
It is recommended that the hot air final consolidation be carried out with the proviso that the resulting nonwoven web or the resulting laminate has a strength in the machine direction (MD) of at least 20 N/5 cm, preferably at least 23 N/5 cm. Particularly preferably, the nonwoven web or laminate has a strength in the machine direction (MD) of more than 25 N/5 cm after the hot air final consolidation.
When producing a nonwoven laminate consisting of two nonwoven webs using a two-beam system, the resulting nonwoven laminate has a thickness in particular of 0.40 mm to 0.80 mm, and preferably of 0.45 mm to 0.70 mm. These thickness data are particularly relevant for nonwoven laminates having an areal weight of 12 to 50 g/ ^m2 .

Preferably, in the process according to the invention, production speeds of at least 100 m/min, in particular at least 200 m/min, are used. Expediently, in the process according to the invention, nonwoven materials or laminates are produced having an areal weight of 12 to 50 g/ ^m2 , preferably 20 to 40 g/ ^m2 .

It is within the scope of the present invention that the filament count used for the nonwoven web or nonwoven laminate is between 1 den and 12 den. According to a highly recommended embodiment, the filament count is between 1.0 den and 2.5 den, in particular between 1.5 den and 2.2 den and preferably between 1.8 den and 2.2 den. In particular, filaments having a count from 1.5 den to 2.2 den, preferably from 1.8 den to 2.2 den, have proven to be very particularly useful within the scope of the present invention.

According to a preferred embodiment of the invention, the hot air pre-solidification is carried out behind the spinning beam in the conveying direction by at least two hot air pre-solidification devices, preferably by at least one hot air knife and at least one hot air oven.
A particularly useful embodiment of the invention is characterized in that between the two hot air preconsolidation devices, in particular between the hot air knife and the hot air oven, there is provided a region of the stacking conveyor in which no process air is suctioned or in which only a very small amount of process air is suctioned. This region is referred to within the scope of the invention as the suction gap or suction gap region. The suction speed here is zero or almost zero or is at least clearly lower than the suction speed _V2 in the second suction region and the suction speed _V3 in the region of the second hot air preconsolidation device or in the region of the hot air oven.
It is important that the suction gap region is arranged on the stacking conveyor or stacking screen belt. If the suction speed _VL in this suction gap region is greater than zero, it is preferably 1% to 15%, in particular 1.2% to 10%, and preferably 1.4% to 8% and very preferably 1.7% to 3% of the suction speed _VH in the upstream main suction region. By this is meant in particular the local minimum value of the suction speed in the suction gap region.
Such suction gaps have proven to be particularly useful within the scope of the present invention, as it has been found that this allows nonwoven webs or nonwoven laminates to be produced with an optimal thickness, which can nevertheless be endowed with sufficient strength.
The suction gap has the further advantage that here additional pre-solidification devices, in particular in the form of roll pairs or compression roll pairs, can be inserted. A particularly advantageous embodiment of the invention is therefore characterized in that the roll pairs or compression roll pairs can be pivoted inwards into the suction gap area and, if necessary, can also be pivoted inwards or removed again.
The length of the suction gap region in the machine direction (MD) or in the transport direction of the nonwoven web/laminate is advantageously from 0.3 m to 5 m, preferably from 1.0 m to 4.5 m and in particular from 1.2 m to 4 m.

The invention is based on the recognition that by means of the device according to the invention and the method according to the invention, nonwoven materials or nonwoven laminates having the desired properties can be produced in a highly targeted and functionally reliable manner, as well as with relatively little effort and, in particular, with little energy consumption, whereby particularly high loft products can be produced easily and without any problems.
It is possible to produce nonwoven materials of relatively high thickness and high flexibility and nevertheless sufficient strength, in particular the nonwoven materials produced according to the invention, to transfer them from the deposition conveyor to a further conveyor for final consolidation.
In addition, the nonwoven material produced according to the invention is characterized by excellent abrasion strength or abrasion resistance.Furthermore, nonwoven materials can be produced which have a very homogeneous surface, which is formed, so to speak, without defects and which does not have any filament agglomerations, in particular due to the blow-back effect.
The method according to the invention can be carried out in a relatively easy and, in particular, low energy consuming manner.

The invention will now be described in more detail with reference to the drawings, which show just one embodiment.

1 is a schematic representation of a longitudinal section of an apparatus according to the invention for the production of spunbond nonwoven materials; FIG. 2 shows, in a schematic illustration, the object according to FIG. 1 in the region of a stacking conveyor with further conveyors or transport belts connected to said stacking conveyor; 1 is a longitudinal section through a two-beam installation according to the invention in a schematic representation; 1 is a schematic representation of a cross-section of an endless filament having an eccentric core-jacket structure, which can be advantageously used within the scope of the present invention.

FIG. 1 shows an apparatus according to the invention for producing a nonwoven material 1 having at least one nonwoven web 2, 3 from fibers made of thermoplastic synthetic material.
These fibres are advantageously, and in this embodiment are, endless filaments F made of a thermoplastic synthetic material. The device illustrated in FIG. 1 is a spunbond device for the production of a nonwoven material 1 made of endless filaments F.

The apparatus comprises a spinning device 10 for spinning out endless filaments F, which are introduced into a cooling device 11 having a cooling chamber 12. Advantageously, and in this embodiment, on two opposite sides of the cooling chamber 12, there are arranged air supply cabins 13, 14 arranged one above the other. From these air supply cabins 13, 14 arranged one above the other, air of different temperatures is introduced into the cooling chamber 12 in an expedient manner.
As recommended, and in this embodiment, a monomer suction device 15 is arranged between the spinning device 10 and the cooling device 11. By means of this monomer suction device 15, interfering gases occurring during the spinning process can be removed from this device. These gases can be, for example, monomers, oligomers or decomposition products and the like.

A drawing device 16 for drawing the endless filaments F is connected downstream of the cooling device 11, preferably and in this embodiment in the direction of filament flow. Advantageously and in this embodiment, the drawing device 16 has an intermediate passage 17, which connects the cooling device 11 with a drawing duct 18 of the drawing device 16.
According to a particularly advantageous embodiment and in this example, the mechanical unit consisting of the cooling device 11 and the stretching device 16, or the mechanical unit consisting of this cooling device 11, the intermediate passage 17 and the stretching duct 18, is formed as a closed mechanical unit, and apart from the supply of cooling air in this cooling device 11, no further air supply from the outside is carried out into this mechanical unit.

Advantageously, and in this embodiment in the direction of filament flow, a diffuser 19 connects with the drawing device 16, through which the endless filaments F are guided. After passing through this diffuser 19, the endless filaments F are deposited on a depositing conveyor, advantageously, and in this embodiment, formed as a depositing screen belt 20.
The depositing screen belt 20 is preferably, and in this embodiment is, configured as an endlessly circulating depositing screen belt 20. The depositing screen belt 20 is expediently designed to be ventilated, so that process air can be sucked in from below through the depositing screen belt 20.

According to an embodiment that has proven useful, and in this example, the diffuser 19, or the diffuser 19 arranged directly above the deposition screen belt 20, has two diffuser walls located opposite each other, with two lower diverging diffuser wall sections 21, 22. These diverging diffuser wall sections 21, 22 are advantageously formed asymmetrically with respect to the central plane M of the device or diffuser 19.
Expediently, and in this embodiment, the inlet-side diffuser wall section 21 forms a smaller angle β with the central plane M than the outlet-side diffuser wall section 22. The angle β that the diffuser wall section 21 forms with the central plane M is preferably at least 1° smaller than the angle β that the diffuser wall section 22 forms with the central plane M.
It is within the scope of the invention that the conveyor-side or screen-belt-side ends of the diverging diffuser wall sections 21, 22 have different distances _e1 and _e2 from the central plane M of the device or diffuser 19. The distance _e1 of the screen-belt-side end of the inlet-side diffuser wall section 21 from the central plane M is less than the distance _e2 of the outlet-side diffuser wall section 22 from this central plane M.
The terms "inlet" and "outlet" refer in particular to the conveying direction of the deposition screen belt 20 or to the conveying direction of the nonwoven webs 2, 3. According to an advantageous embodiment of the invention, the ratio of the spacing e1:e2 is from 0.6 to 0.95, preferably from 0.65 to 0.9 and in particular from 0.7 to 0.9.

It is within the scope of the invention that at the inlet end 23 of the diffuser 19 there are two oppositely positioned secondary air inlet gaps 24, 25, each of which is arranged in one of the two oppositely positioned diffuser walls.
Advantageously, a lower secondary air volume flow rate can be introduced through the secondary air inlet gap 24 on the inlet side relative to the conveying direction of the deposition screen belt 20 than through the secondary air inlet gap 25 on the outlet side. It is recommended that the secondary air volume flow rate of the inlet secondary air inlet gap 24 is at least 5%, preferably at least 10%, and in particular at least 15% less than the secondary air volume flow rate through the outlet secondary air inlet gap 25. This embodiment with different secondary air volume flows in the secondary air inlet gaps is of special importance in view of the solution of the technical problem. The same applies to the asymmetric configuration of the diffuser 19.
It is further within the scope of the invention that at least one suction device is provided, by means of which air or process air is sucked through the depositing screen belt 20 in the depositing region of the endless filaments F in the main suction region 27 or in the main depositing region 26. The main suction region 27 is delimited expediently and in this example below the depositing conveyor or depositing screen belt 20 in the entry region of the depositing screen belt 20 and in the exit region of the depositing screen belt 20, respectively, by suction separating walls 28.1, 28.2.

In a preferred embodiment of the invention, at least one, in particular one, of the suction separation walls 28.1, 28.2 has a separation wall section at its conveyor-side end which is configured as a spoiler section 30. Advantageously and in this embodiment, the spoiler section 30 is configured here, so to speak, as an integral component of the exit-side suction separation wall 28.2 and only as a bent separation wall section of this suction separation wall 28.2. In this preferred embodiment, the spoiler section 30 is expediently configured as a straight or obliquely bent spoiler section 30 with an essentially straight cross section.
Advantageously, and in the embodiment according to Figures 1 and 2, as well as in the first left beam in Figure 3, the spoiler parts 30 are bent towards the side of the associated suction separation wall 28.2 which faces away from the center of the main suction area 27. By contrast, the spoiler parts 30 are expediently bent towards the side of the associated suction separation wall 28.2 which faces towards the center of the main suction area 27, and in this embodiment for the right beam in Figure 3. Different orientations of these spoiler parts 30 in two-beam or multi-beam installations are likewise of special importance within the scope of the present invention.
The advantageously provided spoiler section 30 ensures, in the embodiment according to Figures 1, 2 and 3 (first beam, left side), that there is a continuous, or linear, constant transition of the higher suction speed _VH in the main suction area 27 to a clearly lower suction speed _V2 in the second suction area 29 connected immediately after the main suction area 27.
In the embodiment of FIG. 3 (right side, second beam), the spoiler section 30 bent into the middle of the main suction area 27 ensures that the suction speed _VV in the suction area 33 upstream of this main suction area 27 increases continuously, linearly and constantly to the higher suction speed _VH in the main suction area 27, and in particular without any sudden suction speed increases.

Within the scope of the present invention, it is of particular importance that in the case of a bent spoiler section 30 , the conveyor-side end of this spoiler section maintains a relatively large distance A relative to the depositing conveyor or depositing screen belt 20 .
The distance A is advantageously between 10 mm and 250 mm, preferably between 25 mm and 200 mm, expediently between 28 mm and 150 mm, in particular between 30 mm and 120 mm. According to a highly advantageous embodiment, the distance A is between 20 mm and 160 mm, as has proven useful between 20 mm and 150 mm, and according to one embodiment between 25 mm and 150 mm. In this situation, the distance on the conveyor side of the end of the suction separating wall 28.2 in question is clearly greater than the corresponding distance in the installations known from the prior art.
The invention is based on the recognition that by maintaining this distance A, a particularly gradual and continuous suction speed transition is achieved, which is therefore advantageous, since it avoids adverse effects on the nonwoven web surface or on the nonwoven web surface, which would impair the homogeneity of the nonwoven webs 2, 3. In particular, it avoids or reduces the so-called blowback effect, which is an adverse effect on the filaments of the nonwoven webs 2, 3, which occurs in the event of a sudden suction speed change.
Thus, in many installations known from the prior art, when there is a sudden transition from a high suction speed _VH in the main suction area 27 to a low suction speed in the following area of the deposition screen belt 20, a sucking back or pulling back of the filaments F from the less suctioned area into the more suctioned area takes place. During this blowback effect, undesirable filament agglomerations and associated non-uniformities in the nonwoven webs 2, 3 occur.

According to the invention, at least one hot air pre-solidification device for hot air pre-solidification of the nonwoven webs 2, 3 is provided above the deposition conveyor or deposition screen belt 20. In the embodiment according to FIG. 2, only one spinning device 10 is provided and this device can be used as a one-beam installation. It is recommended that the device corresponding to FIG. 1 is used for this one-beam installation. For the sake of simplicity, in FIG. 2, only the lower part of this spunbonding device or only the lower part of the diffuser 19 of this device is shown. In principle, the installation or device shown in FIG. 2 can also be used in the region of a multi-beam installation.
For the hot air preconsolidation, preferably and in this embodiment, the deposition area 26 is followed first of all by a hot air knife 31, which is followed in the conveying direction of the deposition screen belt 20 by a hot air oven 32. Both hot air preconsolidations are carried out onto one and the same deposition screen belt 20.

The hot air pre-solidification by means of the hot air knife 31 is preferably, and in this embodiment, carried out above the second suction area 29. The suction speed _V2 in this second suction area 29 is preferably, and in this embodiment, a value of from 15% to 50%, in particular from 25% to 40%, of the suction speed _VH in the main suction area 27. As already explained above, the spoiler section 30 in the outlet-side suction separation wall 28.2 ensures a gradual and continuous transition of the high suction speed _VH to the distinctly lower suction speed _V2 in the second suction area 29.
As recommended and in this embodiment, process air is also drawn in from the underside of the hot air oven 32, or this oven operates in a circulating process and also draws in or operates with a suction or process air velocity _V3 , _which expediently has a value of 5% to 30%, in particular 7% to 25%, and for example 7% to 12%, of the suction velocity _VH in the main suction area 27.
Advantageously, the suction velocity decreases from _VH in the main suction zone 27, through _V2 in the secondary suction zone 29, to _V3 below the hot air oven 32 ( _VH > _V2 > _V3 ). According to an embodiment of the present invention, the suction velocity through the deposition screen belt 20 decreases continuously from the main suction zone 27, through the secondary suction zone 29, to the hot air oven 32.
According to another embodiment, it is possible for a non-suctioned or only slightly suctioned area of the deposition screen belt 20 to be arranged between the hot air knife 31 and the hot air oven 32 (so-called suction gap). In this case, the suction speed _VL in this suction gap area 34 can be zero or approximately zero, or it is at least lower than the suction speed _V2 below the hot air knife 31 and, advantageously, also lower than the suction speed _V3 below the hot air oven 32.
Such a suction gap region 34 has proven to be useful for many applications. The invention is therefore based on the realization that with this suction gap region 34, the relatively high desired thickness of the nonwoven webs 2, 3 can be maintained without any problems and nevertheless the required strength of the nonwoven webs 2, 3 in the area of hot air presolidification can be achieved.

It has already been pointed out above that according to a recommended embodiment of the invention, the suction gap area 34 is utilized so that a further pre-solidification device for the nonwoven web can be positioned in the depositing conveyor or depositing screen belt 20. This is, according to an advantageous embodiment of the invention, a roll pair for pre-solidification or a compression roll pair.
This roll pair (not shown in the figures) can be swung, if necessary, closer to the depositing conveyor or depositing screen belt 20 and, if necessary, can likewise be removed again or swung away from contact with the depositing screen belt 20. Such a suction gap region 34 has therefore proven to be particularly useful, in particular between the hot air knife 31 and the hot air oven 32.

The hot air preconsolidation of the nonwoven webs 2, 3 by the hot air knife 31 is advantageously, and in this embodiment is, carried out over a width area in the machine direction (MD) of from 40 mm to 200 mm, in particular from 40 mm to 150 mm. The distance of the at least one hot air nozzle of the hot air knife 31 to the surface of the deposition screen belt 20 is then, as recommended, a value of from 2 mm to 200 mm, and in particular from 3 mm to 100 mm.
Advantageously, the hot air pre-consolidation by the hot air knife 31 is carried out at a hot air temperature of from 80° C. to 250° C., and in particular at a hot air temperature of from 100° C. to 200° C. Hot air temperatures of from 120° C. to 190° C. are advantageous.
As has proven useful, the hot air has a speed of 2 to 5 m/s, preferably 2.2 to 4.5 m/s, during hot air preconsolidation with the hot air knives 31. The distance B of the hot air knives 31 to the central plane M of the device is in particular a value of 100 mm to 1,000 mm, preferably 110 mm to 600 mm and preferably 120 mm to 550 mm. The distance B is measured in particular between the aforementioned central plane M and the first or structural element of the hot air knife 31 which follows in the conveying direction.

In the conveying direction, preferably behind the hot air knife 31 provided for the first hot air preconsolidation, a hot air oven 32 is arranged in this exemplary embodiment. The distance C between the hot air knife 31 and the hot air oven 32 - in the case of the provision of a suction gap region 34 - is expediently a value of between 0.4 m and 5.2 m.
By means of the advantageously provided hot air oven 32, the nonwoven webs 2, 3 are exposed to hot air over a width area in the machine direction (MD) or transport direction of 280 to 2,000 mm, preferably 300 to 1,500 mm. The hot air outlet openings of the hot air oven 32 are then preferably spaced from the surface of the deposition screen belt 20 at a distance of 12 to 200 mm, preferably 25 to 120 mm.
Expediently, the nonwoven webs 2, 3 are presolidified in the hot air oven 32 by hot air at a temperature of from 110° C. to 180° C., in particular from 115° C. to 170° C. and preferably from 120° C. to 160° C. The velocity of the hot air during this hot air presolidification in the hot air oven 32 has proven to be useful, being from 1 to 2.5 m/s, in particular from 1.1 to 1.9 m/s and preferably from 1.2 to 1.8 m/s.
If, within the scope of the invention, no suction gap is produced, the distance between the hot air knife and the subsequent hot air oven is expediently a value of between 0.3 m and 3.0 m.

It is otherwise within the scope of the invention that the hot air pre-consolidation by the hot air knife 31 takes place at a higher hot air temperature than the hot air pre-consolidation by the hot air oven 32. In the embodiment according to Fig. 2, after pre-consolidation by the hot air oven 32, the nonwoven web is transferred from the depositing conveyor or depositing screen belt 20 to a further conveyor in the form of a transport belt 35. Expediently and in this embodiment, the transport belt 35 is an endlessly circulating transport belt 35.
According to a highly advantageous embodiment, and in this example, the surface temperature of the transport belt 35 in the area of the transfer of the nonwoven webs 2, 3 or in the area prior to the hot air final solidification is higher than the surface temperature of the depositing conveyor or depositing screen belt 20 in the area of the transfer of the nonwoven webs 2, 3 to the transport belt 35. Expediently, the surface temperature of the transport belt 35 is at least 5° C., advantageously at least 10° C. and preferably at least 15° C. higher than the surface temperature of the depositing conveyor or depositing screen belt 20 in the area of the transfer of the nonwoven webs 2, 3 described above.
By means of a further conveyor or transport belt 35, the nonwoven webs 2, 3 are fed to a final consolidation, and preferably and in this embodiment to a hot air final consolidation. For this purpose, expediently and in this embodiment, a hot air final consolidation device is provided in the form of a final consolidation hot air oven (through air bonding) 36, as is recommended. Expediently, the nonwoven webs 2, 3 are exposed in this final consolidation hot air oven 36 to a temperature of from 100° C. to 170° C., in particular from 110° C. to 150° C.
The thus finally consolidated nonwoven web 2, 3 or the thus finally consolidated nonwoven material can then be supplied for further use of said nonwoven web or material.

Within the scope of the present invention, this hot air pre-consolidation or pre-consolidation of the nonwoven webs 2, 3 on the depositing conveyor or depositing screen belt 20 is carried out in the following manner:
the nonwoven webs 2, 3 have a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, before transfer from the depositing conveyor or depositing screen belt 20 to the further conveyor or transfer belt 35;
It is important that this is implemented under the following conditions.
This can be achieved without any problems within the scope of the hot air preconsolidation used or described.

In Fig. 3, an advantageous embodiment of the apparatus according to the invention is shown in the form of a two-beam installation with two spinning units 10. The structure of the apparatus components belonging to each beam or each spinning unit 10 preferably corresponds in structure to the spunbonding apparatus above the deposition screen belt 20 shown in Fig. 1 in this embodiment. For the sake of simplicity, these apparatus components are not shown in full in Fig. 3, but rather only the area below the respective diffuser 19. By means of the first spunbonding apparatus components of the two-beam installation according to Fig. 3, the endless filaments F are spun and deposited on the deposition screen belt 20 into a nonwoven web 2. Advantageously, and in this embodiment, by a second spunbonding device component (second beam, right side of FIG. 3 ), endless filaments F are likewise spun and deposited into a nonwoven web 3, which is deposited on top of the first nonwoven web 2, thus forming a nonwoven laminate from both nonwoven webs 2, 3.
Basically, the equipment components or spunbond equipment components illustrated in FIG. 3 can also be used in the area of multi-beam installations having more than two spinning beams or more than two spinning devices 10.

3, each spunbonding device component or each diffuser 19 is followed first of all by a hot air knife 31 for hot air pre-solidification. Advantageously, and in this embodiment, each of the two hot air knives 31 is followed by a hot air oven 32 for further hot air pre-solidification.
The preferred parameters or parameter ranges presented for the example of Fig. 2 for the hot air knife 31 and the hot air oven 32 preferably also apply to the hot air knife 31 and the hot air oven 32 of the two-beam installation of Fig. _3. The same applies correspondingly to the values or ratios/magnitude ratios of the speeds _VH , _V2 , _VL and V3.

The two beams or spunbonding machine components of FIG. 3 differ with regard to the arrangement of the spoiler section 30 in the main suction area 27 of the beam or spunbonding machine component. In the first beam or first spunbonding machine component on the left, the spoiler section 30 connected to the exit-side suction separation wall 28.2 is bent away from the center of the main suction area 27 or from the central plane M to the side of the associated suction separation wall 28.2 that faces away from the center of the main suction area 27. This achieves a continuous or linear, constant transition of the suction speed from the suction speed _VH of the main suction area 27 to the significantly lower suction speed _V2 of the second suction area 29.
In the second beam or second spunbonding device component, on the right side of FIG. 3, a spoiler section 30 is likewise connected to the suction separation wall 28.2 on the exit side of the main suction area 27. Here, however, this spoiler section 30 is advantageously and in this embodiment bent towards the center of the main suction area 27 or towards the central plane M. This configuration of the spoiler section 30 achieves a continuous or linear, constantly increasing suction speed from the relatively low suction speed _VV of the upstream suction area 33 to the clearly higher suction speed _VH of the main suction area 27.

Within the scope of the present invention, according to an advantageous embodiment and in this example, it is important that both nonwoven webs 2, 3 are deposited on the same depositing conveyor or on the same depositing screen belt 20 and are likewise subjected to all hot air pre-solidification on this depositing conveyor or depositing screen belt 20.
Only subsequently is the nonwoven laminate consisting of the nonwoven webs 2, 3 transferred from the depositing conveyor or depositing screen belt 20 to a further conveyor in the form of a transport belt 35, on which the final consolidation takes place. The advantageous features and parameters presented in connection with Fig. 2 for the hot air final consolidation device also apply in relation to the hot air final consolidation of Fig. 3. The same applies correspondingly with regard to the temperature or surface temperature of the depositing conveyor or depositing screen belt 20 and of the further conveyor or transport belt 35.

Advantageously, and in the embodiment according to FIG. 3, the hot air preconsolidation of the first nonwoven web 2 and the hot air preconsolidation of the laminate consisting of both nonwoven webs 2, 3 are carried out in a manner similar to that described above.
the laminate has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, before delivery to a further conveyor or transport belt 35;
This is done under the following conditions.

According to a highly advantageous embodiment, the device according to the invention and the method according to the invention produce endless filaments F in the form of bicomponent or multicomponent filaments and deposit these endless filaments F in the form of crimped endless filaments F onto the nonwoven webs 2, 3.
"Crimped" here means that the crimped filaments each have crimps with at least 1.5 loops, advantageously 2 loops, preferably 2.5 loops, very preferably 3 loops per centimeter of the length of the filament. According to a preferred embodiment, the crimped filaments each have 2 to 3 loops per centimeter of the length of the filament. The number of crimped loops or crimped loops per centimeter of the length of the filament is measured, in particular according to the Japanese JIS standard L-1015-1981, in such a way that the crimps are counted in (1/10 mm) under a preload of 2 mg/den, the unstretched length of the filament being the basis. A sensitivity of 0.05 mm is used to define the number of crimped loops.
This measurement is expediently carried out by means of a "Favimat" - Geraet der Firma TexTechno, Deutschland ("Favimat" measuring instrument from the company TexTechno, Germany). For this purpose, reference is made to non-patent document 1. For this purpose, filaments or filament specimens are removed from the deposition or deposition screen belt as filament balls before further solidification, and the filaments are individualized and measured.

The crimping of the filaments is preferably achieved by the use of endless filaments having an eccentric core-sheath structure. Advantageously, this type of bicomponent filament having an eccentric core-sheath structure is produced in a two-beam installation of FIG. 3 having both spunbonding equipment components or both beams.

4 shows bicomponent filaments with an eccentric core-sheath construction, which are treated with very particular advantage within the scope of the present invention. In this case, a cross section of an endless filament F with a special advantageous core-sheath construction is shown in FIG. 4. In this case, the sheath 37 has a constant thickness d in the filament cross section, preferably and in this embodiment over more than 50%, preferably over more than 55%, of the filament circumference. Preferably and in this embodiment, the inner core 4 of the filament F occupies more than 65% of the area of the filament cross section of the filament F.
Preferably and in this embodiment, the inner core 4 is formed - viewed in the filament cross section - in the shape of a circular segment. Expediently and in this embodiment, the inner core 4 has, with respect to its outer circumference, a circular arc-shaped outer periphery 5 and a linear outer periphery 6. Advantageously and in this embodiment, the circular arc-shaped outer periphery of the inner core 4 occupies more than 50%, preferably more than 55%, of the outer circumference of the inner core 4.
Expediently and in this embodiment, the jacket 37 of the filament F is formed - viewed in the filament cross section - in the shape of a circular segment outside the jacket region with a constant thickness d. This circular segment 7 of the jacket 37 preferably and in this embodiment has, with respect to its circumference, a circular arc-shaped peripheral portion 8 and a linear peripheral portion 9. The thickness d or average thickness d of the jacket 37 in the constant jacket region is preferably 0.5% to 8%, in particular 2% to 10%, of the filament diameter D. In this embodiment, it is possible for the thickness d of the jacket 37 to be 0.05 μm to 3 μm in the constant jacket thickness region.

Claims (21)

An apparatus for the production of a nonwoven material (1) having at least one nonwoven web (2, 3), comprising:
at least one spinning device (10) or at least one spinning beam for spinning out fibers is provided, and a depositing conveyor, in particular a depositing screen belt (20), on which the fibers can be deposited into a nonwoven web (2, 3),
At least one hot air pre-solidification device is provided for hot air pre-solidification of the nonwoven web (2, 3) on the depositing conveyor or on the depositing screen belt (20),
in the conveying direction of the nonwoven web (2, 3), a further conveyor - in particular in the form of a transport belt (35) - is arranged behind the depositing conveyor for receiving the pre-consolidated nonwoven web (2, 3) from the depositing conveyor, and at least one final consolidation device - in particular at least one hot air final consolidation device - is provided for final consolidation or hot air final consolidation of the nonwoven web (2, 3) on the further conveyor or on the transport belt (35),
The hot air pre-solidification of the nonwoven web (2, 3) is carried out on the depositing conveyor or depositing screen belt (20),
the nonwoven web (2, 3) has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, before being transferred to the further conveyor or the transport belt (35);
and
the temperature of the surface of the further conveyor, in particular the transport belt (35), is higher in the conveying direction than the temperature of the surface of the depositing conveyor or depositing screen belt (20) in the area of the transfer of the nonwoven web or the laminate to the further conveyor before the hot air final solidification device,
An apparatus comprising: The nonwoven material (1) is a nonwoven laminate consisting of at least two nonwoven webs (2, 3) and is provided with at least two spinning devices (10) or spinning beams ,
A first spinning device (10) or a first spinning beam is provided for spinning a first fiber, said first fiber being capable of being deposited on said depositing conveyor or depositing screen belt (20) into a first nonwoven web (2);
a second spinning device (10) or a second spinning beam is provided for spinning out a second fiber, which is downstream of the first spinning beam in the conveying direction of the depositing conveyor, and the second fiber can be deposited on the depositing conveyor or on the first nonwoven web (2) into a second nonwoven web (2); between the first spinning beam and the second spinning beam , at least one hot air pre-solidification device is provided as at least one first hot air pre-solidification device for the hot air pre-solidification of the first nonwoven web (2);
at least one second hot-air pre-consolidation device for the hot-air pre-consolidation of the second nonwoven web (3) or of the laminate consisting of the first and second nonwoven webs (2, 3) is arranged behind the second spinning beam in the conveying direction of the fiber deposit,
the laminate can be or is delivered from the depositing conveyor to the further conveyor, in particular in the form of the transport belt (35),
the laminate is final solidified on the further conveyor by the final solidification device, in particular the hot air final solidification device, and
The hot air pre-consolidation of the nonwoven web (2) or the laminate on the depositing conveyor comprises:
the laminate has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, prior to delivery to the further conveyor;
This is possible under the condition that
2. The apparatus of claim 1 . At least one spinning device (10) or at least one spinning beam comprises:
It is designed as a spunbonding device for producing a spunbond nonwoven material made of endless filaments,
3. Apparatus according to claim 1 or 2. at least one of the spinning devices (10) or at least one of the spinning beams is configured for the production of bicomponent or multicomponent fibers, in particular bicomponent or multicomponent filaments,
4. Apparatus according to claim 1, characterized in that The device is configured for producing at least one nonwoven material or at least one nonwoven web (2, 3) from crimped fibers or crimped endless filaments.
5. Apparatus according to any one of claims 1 to 4. For the fibers spun by at least one spinning beam ,
at least one cooling device (11) for cooling these fibers;
This cooling unit (11) is followed by at least one drawing unit (16) for drawing the fibers,
Advantageously, this drawing device (16) is followed by at least one diffuser (19),
6. Apparatus according to any one of claims 1 to 5. The mechanical unit consisting of the cooling device (11) and the stretching device (16) is formed as a closed mechanical unit, and
No further air can be supplied from the outside into the mechanical unit, except for the supply of cooling air in the cooling device (11).
7. The apparatus according to claim 6 . the hot air pre-solidification device being in the form of at least one hot air knife (31) and/or in the form of at least one hot air oven (32),
8. Apparatus according to any one of claims 1 to 7. the first hot air pre-solidification device between the first and second spinning beams is formed in the form of at least one first hot air knife (31) and/or in the form of at least one first hot air oven (32),
8. Apparatus according to any one of claims 2 to 7. in the conveying direction of the first nonwoven web (2), firstly at least one first hot air knife (31) is downstream of the first spinning beam , and
at least one first hot air oven (32) is downstream of this first hot air knife (31) before the second spinning beam ,
10. The apparatus of claim 9. the second hot air pre-solidification device behind the second spinning beam ;
in the form of at least one second hot air knife (31) and/or in the form of at least one second hot air oven (32),
10. Apparatus according to any one of claims 2 to 9. in the conveying direction of the laminate, firstly at least one second hot air knife (31) is downstream of the second spinning beam , and
This first hot air knife (31) is followed by at least one second hot air oven (32).
12. The apparatus of claim 11 . a hot air knife (31) which exposes the nonwoven web (2) or the laminate to hot air over a width area in the machine direction (MD) of from 15 mm to 300 mm, in particular from 30 mm to 250 mm, advantageously from 40 mm to 200 mm, and preferably from 40 mm to 150 mm; and/or
the distance of at least one hot air nozzle of the hot air knife (31) to the surface of the depositing conveyor or the surface of the depositing screen belt (20) is between 2 mm and 200 mm, in particular between 3 mm and 100 mm;
13. Apparatus according to any one of claims 8 to 12. The hot air oven (32) exposes the nonwoven web (2) or the laminate to hot air over a width area in the machine direction (MD) of 280 mm to 2,000 mm, in particular 290 mm to 1,800 mm and preferably 300 mm to 1,500 mm, and/or
the hot air outlet openings of the hot air oven (32) are spaced from the surface of the stacking conveyor or the surface of the stacking screen belt (20) by a distance of 12 mm to 200 mm, in particular from 20 mm to 150 mm, and preferably from 25 mm to 120 mm,
14. Apparatus according to any one of claims 8 to 13. A method for producing a nonwoven material (1) having at least one nonwoven web (2, 3), comprising the steps of:
Fibers are spun and deposited onto the nonwoven web (2, 3) on a depositing conveyor, in particular a depositing screen belt (20),
the nonwoven fabric is pre-solidified on the depositing conveyor by hot air and the nonwoven web (2, 3) is transferred from the depositing conveyor or depositing screen belt (20) to a further conveyor or transport belt (35) and there, in particular, is final consolidated,
The hot air presolidification
the nonwoven web (2, 3) has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, before being transferred to the further conveyor;
and
the temperature of the surface of the further conveyor, in particular the transport belt (35), is higher in the conveying direction than the temperature of the surface of the depositing conveyor or depositing screen belt (20) in the area of the transfer of the nonwoven web or the laminate to the further conveyor before the hot air final solidification device,
A method comprising: A nonwoven laminate is produced from at least two nonwoven webs (2, 3), at least one of the nonwoven webs (2, 3) having crimped fibers, a first fiber being spun and deposited onto a first nonwoven web (2) on a depositing conveyor, in particular a depositing screen belt (20),
Second fibers are spun and these second fibers are deposited on the first nonwoven web (2) into a second nonwoven web (3) or into the laminate consisting of both nonwoven webs (2, 3);
After the deposition of the first fibers and before the deposition of the second fibers, the first nonwoven web (2) is pre-solidified by hot air, and after the deposition of the second fibers, the second nonwoven web (3) or the laminate (1) consisting of the first nonwoven web (2) and the second nonwoven web (3) is pre-solidified by hot air,
The laminate (1) is transferred from the depositing conveyor or depositing screen belt (20) to the further conveyor or transfer belt (35) and the hot air pre-solidification is carried out
the laminate (1) has a strength in the machine direction (MD) of 0.5 to 5 N/5 cm, in particular 0.7 to 3.5 N/5 cm, and preferably 0.8 to 3.5 N/5 cm, before or during delivery to the further conveyor;
This is carried out under the condition that
16. The method of claim 15. the fibers, in particular the fibers of the first spinning beam and/or the fibers of the second spinning beam , are spun as spunbond filaments or endless filaments, in particular as bicomponent or multicomponent filaments, and
Advantageously, it is deposited as crimped filaments, in particular onto the first nonwoven web (2) and/or onto the second nonwoven web (3),
17. The method according to claim 15 or 16. the fibers, in particular the fibers of the first spinning beam and/or the fibers of the second spinning beam , are spun as bicomponent or multicomponent filaments having an eccentric core-sheath structure;
18. The method according to any one of claims 15 to 17. the nonwoven webs, in particular the first nonwoven web (2) and/or the laminate consisting of the first nonwoven web (2) and the second nonwoven web (3), are pre-consolidated by hot air using a hot air knife (31),
This hot air preconsolidation is carried out at a hot air temperature of from 80° C. to 250° C., in particular from 100° C. to 200° C. and preferably from 120° C. to 190° C., respectively; and/or
The hot air has a velocity during the hot air presolidification of 1.9 to 8 m/s, in particular 2 to 5.5 m/s and preferably 2.2 to 5.5 m/s.
19. The method according to any one of claims 15 to 18. the nonwoven webs, in particular the first nonwoven web (2) and/or the laminate consisting of the first nonwoven web (2) and the second nonwoven web (3), are pre-solidified by hot air using at least one hot air oven (32), and
This hot air presolidification is carried out with hot air at a temperature of from 110° C. to 180° C., in particular from 115° C. to 170° C. and preferably from 120° C. to 160° C.; and/or
The hot air in the hot air presolidification has a velocity of 1 to 2.5 m/s, in particular 1.1 to 1.9 m/s and preferably 1.2 to 1.8 m/s.
20. The method according to any one of claims 15 to 19. The surface temperature of the further conveyor in the area before the hot air final solidification or in the area of the delivery of the nonwoven webs (2, 3) or the laminate is
higher than the surface temperature of the depositing conveyor or depositing screen belt (20) in the area of the delivery of the nonwoven web (2, 3) or the laminate to the further conveyor, and
The surface temperature of the further conveyor is
at least 5° C., advantageously at least 10° C. and preferably at least 15° C. higher than the surface temperature of the depositing conveyor in the area of the transfer of the nonwoven web (2, 3) or the laminate (1) to the further conveyor,
21. The method according to any one of claims 15 to 20.