DE102005054726A1 - Nonwovens and process for their preparation - Google Patents

Abstract

Described are nonwovens containing threads not produced in the spunbonded nonwoven process, for example made from non-melt-spinnable fiber-forming materials. DOLLAR A By using these threads in combination with filaments produced in the spunbond process, new nonwovens with novel combinations of properties can be produced. DOLLAR A The production can take place on conventional spunbond systems in which some of the stretching devices are used as conveyors for the threads not produced in the spunbond process.

Description

The The present invention relates to new nonwovens, new processes for the production of nonwovens and their use in textiles and technical applications.

Textile sheet have been known for a long time. The techniques for production of these fabrics are subject to constant improvements.

So belongs though the loom is among the oldest machines the world, but is still improving today. Even though the web speeds partly because of the increase the firing speeds could be increased however, it is based on the process itself that the weft on both edges the textile is brought to a zero speed before it again in the opposite direction can take his way.

Also Knitting is a very old surface forming technique that is machine-made accomplished can be. Knitting is a guided placement process every single thread, or in modern circular knitting machines also in a group of threads.

Both The method described above has in common that it is continuous Threads as Use semi-finished goods.

Further textile fabrics are felt and loden. A felt is made by forging or needling several over each other lying layers in particular of woolen threads. So can a felt also be considered as a non-woven wool fabric. Loden be first woven from woolen yarns and the woolen fabric thus obtained by Walken felted into a so-called loden. It is about a (often unwanted) hooking of the wool fibers due to erecting dandruff.

A another group of textile fabrics form the fleeces. these can be prepared by wet or dry methods.

at In wet-laid fabric production, short fibers are used in high dilution Stirred up water and over a filing screen separated from the water and then chemically or thermally connected together to a fleece. A high degree of dilution in the water and a short fiber length guarantee, that the fibers of different origin neither interlock with each other can still agglomerate with each other. In this way, a very high degree of uniformity of the distribution of Fibers over the area be achieved. However, the obtained sheets are not mechanically strong load.

at dry nonwoven fabric making are fibers of finite length opened in the preparation precursor fiber bales, if necessary mixed with other fiber types, in a carding machine into one Preferred direction "combed" wherein a batt arises. Several layers of this batt are superimposed laid ("dished"), whereby by the Ablagebewegungen set limits preferred directions of the fibers can be and these layers then perpendicular to the nonwoven plane by any solidification be converted into a fleece. This technique granted a high productivity with high uniformity the fiber tray. The mixture of fibers allows within wide limits an adaptation to desired Surface characteristics of products. To the mechanical resistance, such as. Pilling or washing resistance, to increase, a high proportion of touching intersection points must be chemical or thermally solidified into so-called bonding points. The bending stiffness increases and the fabric loses drapability.

at Spunbond fabrications are granules of one or more melt-spinnable polymers each melted in an extruder, through a spinneret pressed, mechanically or pneumatically stretched and placed on a storage belt. The unconsolidated nonwoven fabric is then analogous to those described above Non-woven fabric mechanically stabilized.

To A few years ago, this process was used to produce fabrics used, e.g. For the use as a carrier for roofing membranes or as a carrier for carpet fibers were intended and to which, as a rule, no claims to their textile draping were made. Spunbonded fabrics are by one to other nonwoven types comparatively poor uniformity and by comparatively high mechanical loads characterized.

Spunbond lines stand out in comparison to other textile surface forming techniques a high productivity out. This requires high investment costs and when changing the polymers very high changeover times and costs. These factors have the consequence that such investments only can be operated comparatively inflexible and are constantly kept in operation have to.

All nonwoven fabric types are based on the fact that the fibers forming them are stacked on top of each other in several layers (placed in the xy plane), and that the resulting mecha nisch unstable nonwoven fabric then still needs to be consolidated in z-direction. The chemical or thermal bonding processes cause a decrease in drapability.

nonwovens have the advantage over the other textile fabrics that in these the plastic granules or fibers directly into the finished fabrics are transferred. On the other hand when weaving or knitting the yarns only through a complex Fabric-forming process be transferred to the textile surface.

In The prior art has already been proposed to filaments their production and then these products in a surface formation process contribute.

So For example, US-A-3,921,265 and US-A-3,885,279 describe a process for producing a textile fabric and a device suitable therefor, where threads over several Store shelves for storage. Described there is a directed filing of the threads and no web forming process known to be through statistical Tray is marked. Furthermore There is no information on the nature of the deposited threads.

in the DE patent 816,215 discloses a device for producing mats or webs of glass fibers or the like Fibers described. Several threads are combined in a mechanical conveyor and twisted as strand stranded on a surface to the mat. The Storing the strands done by transport by means of a blower. Depending on its setting the tray can be varied. More details, in particular a statistical storage of strands, are not disclosed in this document. The strands remain in the fabric receive.

In DE-A-3,012,806 discloses a tufted carpet with a secondary backing a continuous filament nonwoven fabric of several layers of confused filaments Polyesters described in crossed Parallel texture are arranged. The nonwovens can be spun out by grouping or by jointly stripping or unwinding of polyester threads and their common storage to a fleece with crossed parallel texture be generated. The use of non-melt spinnable fibers is not to refer to this document.

In DE-A-3,630,392 discloses a process for the production of solidified Fleeces for the uptake of water and / or substances with oleophilic and / or lipophilic properties described. The web formation takes place by direct blow spinning on a receiving device.

Out EP-A-281,865 are bonded sheets of inorganic Fibers, such as waterglass or silica fibers known. The fleece formation is done by directly processing the spun fibers Drying or Wet-laying techniques. The fibers are made by a heat treatment at temperatures above 50 ° C connected with each other. Due to the comparatively low bonding temperatures have to the spun fibers are processed immediately.

Out US-A-5,660,910 are nonwoven webs having improved tear strength known. In addition to matrix filaments, these nonwovens have reinforcing filaments rough titer on. In addition to the spunbonding is also the Processing pre-spun and intermediate filaments to nonwovens. These are through a suction device placed directly on a conveyor belt. A statistical filing the intervening filaments is not disclosed. Also the uniformity The nonwoven fabric produced is due to the use of coarse filaments Set limits.

In DE-A-4,115,190 nonwovens of films are disclosed, which have a very uniform fair distribution with a high basis weight of more than 250 g / m ² . To produce these nonwovens, filaments (bundles) of various materials are disrupted by air nozzles in individual filaments, deposited extremely evenly on a moving surface and then solidified in a manner known per se. Low basis weight nonwovens and even fair distribution are not disclosed. Especially such nonwovens are difficult to produce, since in nonwovens with high basis weights and correspondingly high number of fibers per unit of space resulting irregularities are more likely. As fiber materials only thermoplastic spinnable materials are disclosed.

outgoing from this prior art, it is an object of the present invention To provide nonwovens with a very high uniformity.

A Subgroup of new nonwovens concerns products that have so far non-woven non-woven fabrics include endless filaments. In this way let yourself the range of possible Nonwovens as well as their property profiles and fields of application expand.

The present invention relates to nonwovens having a basis weight of up to 250 g / m ² and with a high uniformity, expressed by a mass variation coefficient of the basis weight distribution CV of less than 10%, which contain randomly deposited filaments of non-spunbonded filaments.

In In another embodiment, the invention relates to nonwovens containing statistically deposited filaments of non-melt spinnable Materials.

Under The term "thread" or "threads" is intended in the context of this Description a structure constructed of fibers or filaments in which a dimension called "length" is the other two The dimensions describing the cross section of the thread by several Exceeds orders of magnitude and their titres range from 0.1 dtex to 100 tex. Typical thread lengths range from several meters to several thousand Kilometers.

Under The term "fiber" or "fibers" is intended in the context of this Description a structure of finite length can be understood at a dimension called "length" the other two, the cross-section of the fiber describing dimensions by several Exceeds orders of magnitude and their titres range from 0.1 dtex to 100 tex. typical fiber lengths range from one millimeter to a few centimeters.

Under The term "filament" or "filaments" is intended in this context Description a structure understood in which a dimension called "length" the other two, the cross section of the filament describing dimensions by several Exceeds orders of magnitude and their titres range from 0.1 dtex to 100 tex. Typical filament lengths range from several meters to several thousand kilometers.

Threads in the sense this description may be filament yarns, Fiber yarns, monofilaments (wires) as well To be twisted.

Fiber-forming Materials which build up the threads used according to the invention, are not subject to any restrictions. It can various materials or material mixtures used become. Examples of this are threads made of synthetic and / or natural fiber-forming materials, such as thermoplastic polymers, natural products such as cellulose, modified cellulose or proteins, or of inorganic materials, such as carbon, metals or glass or filaments that are made by peeling processes can be won such as polytetrafluoroethylene filaments. In addition to homofilaments or fibers and multicomponent filaments or - fibers be used.

Under "Nonwoven from statistically deposited threads "should in the context of this Description a nonwoven fabric to be understood by filing of threads has been generated on a moving transport device, the filing of the threads on the transport device takes place in several layers and not the threads be stored down to a previously directed storage point and thus run independently in the individual layers. The filing of the threads can be done with or without alignment to a predetermined location, wherein the exact location due to the filing process not specified is.

Of the Nonwoven fabric according to the invention can be made from a variety of different materials and material combinations consist.

One Characteristics of the nonwoven fabric according to the invention is that at least some of the threads are not in the spunbonding process has been produced. In contrast to the conventional spunbonding process, in which the production of filaments directly with the formation of textile surface coupled here is at least a part of the threads in one or more upstream step (s) generated, cached or not in the spunbonded plant, but in one of these upstream produced other spin line and then used in web formation. So there are threads used, which have not been generated in the web forming plant are. A group of these threads can Fibers or filaments of materials that in the conventional Spunbond process can not be produced. This approach allows the production of nonwovens from novel material (combinations). A second group of these threads can Having fibers or filaments of melt-spinnable materials, in spunbond processes not or only with increased effort can be generated and therefore expediently produced in a plant upstream of the web formation have been.

One example for The first group of materials are filaments of non-melt spinnable Materials, such as cellulose threads.

One example for the second group are threads containing fibers or filaments of the POY type ("partially-oriented-yarn") or filaments containing Containing fibers or filaments of the FOY ("fully-oriented-yarn") type or filaments Fibers or filaments with an additive used in the spunbonding process can not or can only be spun with difficulty or Containing threads high-strength fibers or filaments, which by high draw after have been generated in the spinning.

The used according to the invention, Non-spun yarns can be completely off non-melt spinnable materials; but you can also from combinations of these fibers or filaments with others Fibers or filaments of thermoplastically spinnable materials consist; and / or they are made of thermoplastic spinnable and accessories containing materials; and / or they are made of thermoplastic spinnable materials after spinning in a way have been treated, usually not possible in spunbonded plants is such as a multiple stretching with very high degrees of stretching, optionally followed by a relaxation step.

The Type of thread-forming techniques plays in the production of the Threads off non-thermoplastic spinnable materials or thermoplastic spinnable materials do not matter. It may be after the wet spinning process, the dry spinning process, the wet dry spinning process, the gel spinning process, the peeling process or continuous filaments obtained by the matrix spinning process which are not or only with difficulty in the spunbond process can be produced, or it can Fiber yarns that have been produced by secondary spinning process.

The Nonwoven fabrics according to the invention are characterized by a very high uniformity. This is expressed by a mass variation coefficient of the basis weight distribution CV of less than 10%, preferably less than 7%.

The mass variation coefficient of the basis weight distribution is determined by the following method:
2 rows of 19 specimens of 5 × 5 cm ² are punched out per meter across the width of the flat goods web, with the second row being offset by half a specimen for the first.

60 specimens of 5 × 5 cm ^{2 are} punched out in a row one behind the other in the direction of travel over the length of the flat product web.

The basis weight x _{i of} each test piece i is converted into g / m ² . Since each specimen has the area of 0.0025 m ² , its basis weight must be multiplied by 400 in order to arrive at the grammage of g / m ² relative to 1 m ² .

X

= mittleres Flächengewicht des Vliesstoffes in g/m²

x_i

= Gewicht des Prüflings i in g/0,0025 m²

n

= Anzahl der Prüflinge

The coefficient of variation is determined as follows: CV = (Et * 100) / X (%) in which Et = (Σ (x i - X) 2 / N) ½ X = (Σx i · 400) / n and

X

= mean basis weight of the nonwoven fabric in g / m ²

x _i

= Weight of the test piece i in g / 0.0025 m ²

n

= Number of candidates

The Form of the used for the production of the nonwoven fabric according to the invention Threads can chosen arbitrarily become. In addition to mono- and multifilaments staple fibers or Twists are used.

Prefers Nonwovens are made completely Containing threads Fibers or filaments of non-thermoplastic spinnable fiber-forming materials consist.

Further preferred nonwovens consist or contain besides fibers or Filaments of non-thermoplastic spinnable fiber-forming materials additionally Threads off Fibers or filaments of melt-spinnable fiber-forming materials.

Further preferred nonwoven fabrics contain threads of POY fibers or POY filaments or of FOY fibers or FOY filaments. These POY fibers or POY filaments or FOY fibers or FOY filaments are used on very high spinners Deduction speeds generated and then optionally stretched. This results in fibers or filaments with very high strengths, which on today's spunbond systems only with difficulty can be produced.

Furthermore, preferred nonwovens contain threads made of high-strength plastic fibers or high-strength Plastic filaments, in particular of polyester. These fibers or filaments are produced by melt or solution spinning and then high stretched. This results in fibers or filaments with very high Strengths, which likewise on today's spunbond plants only under Difficulties can be made.

Further preferred nonwovens contain threads of metal or of metal alloys.

Further preferred nonwovens contain threads of additized plastics, most preferably spun-dyed and / or flame-retardant plastics. These fibers or filaments are made by solution spinning or melt spinning produced by additivierten spinning masses and then stretched. This results in additized fibers or filaments based on conventional Spunbonding systems can not be produced.

preferred examples for non-melt-spinnable fiber-forming materials are cotton, wool, Cellulose and cellulose derivatives (such as viscose, modal, copper silk, Cellulose acetates, half or triacetates), polyacrylonitrile, aromatic Polyamides (aramids), non-thermoplastic polyurethanes, non-melt spinnable halogenated polyolefins such as polytetrafluoroethylene, polyvinyl chloride or polyvinylidene chloride, as well as rubbers, polyvinyl alcohol or Carbon.

Cellulosic fibers or filaments are preferably understood as meaning the viscose fibers or filaments obtained by the viscose process. It may also be obtained by the solution spinning process fibers or filaments, for example, ^® lyocell fibers or ^® Lyocell filaments.

Under Cellulose derivative fibers or filaments become fibers or filaments understood as derived from chemically modified cellulose, for example of cellulose acetate or cellulose half acetate.

preferred examples for Melt-spinnable fiber-forming materials are melt-spinnable thermoplastic Polycondensates, for example polyesters, such as polyethylene terephthalate, Polybutylene terephthalate or polylactides, or aliphatic or aliphatic-aromatic Polyamides, such as polyamide 6, polyamide 6,6, or polyether ketones, polyarylene sulfides, Polyarylene ether sulfones, polycarbonate, or proteins and protein derivatives, such as gelatin, chitin or alginates, as well as melt-spinnable thermoplastic polymers, such as polyolefins, in particular polypropylene, polyethylene or their Copolymers, or the thermoplastic polyurethanes including the thermoplastic Polyurethane elastomers, and other melt-spinnable materials, like glass or metals including of metal alloys.

Especially preferred are melt-spinnable fiber-forming materials melt-spinnable thermoplastic polycondensates or melt-spinnable used thermoplastic polymers.

In a further preferred embodiment According to the invention, the nonwovens additionally contain statistically deposited and filaments produced in the spunbond process, in particular multi-component filaments in the form of split filaments that are not at least two together compatible, splittable, melt-spinnable and fiber-forming polymers have, preferably split filaments of the combination polyester / polyamide, Polyester / polyolefin, polyamide / polyolefin, polyolefin / polyolefin, Polyester / polyurethane, polyamide / polyurethane, polyolefin / polyurethane.

such fissile filaments and nonwovens made therefrom are on known, for example from US-A-5,970,583.

All Nonwoven fabrics whose threads are exclusively made from are particularly preferred Filaments and / or spun yarns of non-melt-spun fiber-forming fibers Materials exist.

A variant of the nonwoven fabrics according to the invention may have any basis weights adapted to the particular application. Examples of basis weights are 15 to 1000 g / m ² , preferably 50 to 600 g / m ² , in particular 50 to 250 g / m ² .

Another variant of the nonwovens according to the invention has basis weights of up to 250 g / m ² , preferably 15 to 250 g / m ² , in particular 20 to 150 g / m ² .

The used in the nonwovens according to the invention Filaments and / or fiber yarns can be any and have adapted to the particular application titres. Examples for this Titers are 0.05 to 200 dtex, preferably 0.15 to 150 dtex.

Next Filaments and / or fiber yarns from homofil fibers can also those of heterofil fibers, for example bicomponent fibers, in ruffled or uncrimped Form or mixtures of different fiber types are used.

In the nonwovens of the invention the threads are common in no preferred direction, i. isotropic, filed. The nonwoven fabric may consist of the same or different titers of the same threads. The non-woven fabric building threads can be constructed of different filaments and / or fibers, for example from homofil fibers or filaments, but also from 100% bicomponent fibers or filaments or a blend of bicomponent fibers or filaments and homofil fibers or filaments. It can also be mixtures of threads be used from synthetic fibers or filaments with natural fibers.

The use of yarn materials not previously used in spunbonded fabrics, optionally in combination with yarn materials used in conventional spunbonded fabrics, makes it possible to produce novel nonwovens with novel property combinations. For example, by depositing metal filaments nonwovens with electrical and thermal conductivity can be produced or by depositing filaments correspondingly additized in the spinning composition it is possible to produce spun-dyed or flameproofed fabrics Nonwovens produce or by depositing high-strength threads can be nonwovens produce particularly high skills.

With the method described can be textile fabrics generate, in terms of the range of variation of their properties correspond to the tissues, but in contrast to these statistically discarded threads exhibit. Furthermore, it is possible to produce textile fabrics in which fiber blends as are possible with staple fiber webs, but with much higher and more durable resistances, as in the nonwoven fabrics according to the invention - similar to in the tissues - the Threads in the structure of the fabric are installed. This leads for a number of properties, such as maximum tensile strength, washability, the tear strength (WRK) and the pilling behavior (abrasion) to significantly improved Values.

The Nonwoven fabrics according to the invention can after being deposited on the transport device in mechanically stabilizing and further processing known manner.

Directly after depositing in several layers does not mechanically stable and unmanageable unbonded web, by intertwining the individual layers must be stabilized. This is done by Use of mechanical, hydromechanical, pneumatic and / or thermal process and / or by using chemical binders.

Especially Preferably, the solidification of the nonwoven fabric by the use mechanical, hydromechanical and / or thermal processes, in particular through the use of needle chairs or water jets.

The Nonwoven fabrics according to the invention can more Additives commonly used in nonwovens, contain. examples for such additives are finishes, lubricants, antistatic agents, biocides, Antioxidants, electrical conductivity imparting additives, adsorbents or fillers.

By The present invention will be a new and simple process provided for the production of nonwovens, which is characterized by a high productivity and flexibility distinguished. Also allowed the process the production of nonwovens from materials, the so far not or only with difficulty to nonwovens containing endless threads were to be processed.

• i) Vorlage mehrerer Vorratseinrichtungen A mit Fäden, insbesondere mit Fäden enthaltend Fasern oder Filamente aus nicht-schmelzspinnbaren Materialien,
• ii) gegebenenfalls Vorlage weiterer Vorratseinrichtungen B mit Fäden, die sich von den in Vorratseinrichtungen A befindlichen Fäden unterscheiden,
• iii) Abziehen der Fäden von Vorratseinrichtungen A durch mindestens eine Fördereinrichtung, vorzugsweise durch mehrere Fördereinrichtungen,
• iv) statistisches Ablegen der in Schritt iii) abgezogenen Fäden in Form eines ungebundenen Vlieses und in mehreren Schichten auf eine Transportvorrichtung,
• v) gegebenenfalls Abziehen der Fäden von Vorratseinrichtungen B durch mindestens eine Fördereinrichtung, vorzugsweise durch mehrere Fördereinrichtungen,
• vi) gegebenenfalls statistisches Ablegen der in Schritt v) abgezogenen Fäden in Form eines ungebundenen Vlieses und in mehreren Schichten auf eine Transportvorrichtung, und
• vii) Verfestigen des erhaltenen unverfestigten Vlieses durch an sich bekannte mechanische, hydromechanische, pneumatische und/oder thermische Verfahren und/oder durch Einsatz chemischer Binder.

The invention also relates to a process for producing nonwovens comprising the measures:

• i) presentation of a plurality of storage devices A with threads, in particular with threads containing fibers or filaments of non-melt-spinnable materials,
• (ii) where appropriate, the provision of further stockpile arrangements B with yarns other than those in stocking equipment A,
• iii) removing the threads of supply devices A by at least one conveyor, preferably by a plurality of conveyors,
• iv) statistically depositing the threads withdrawn in step iii) in the form of an unbonded nonwoven and in a plurality of layers on a transport device,
• v) optionally withdrawing the threads of supply devices B by at least one conveyor, preferably by a plurality of conveyors,
• vi) optionally random depositing the threads withdrawn in step v) in the form of an unbonded nonwoven and in a plurality of layers on a transport device, and
• vii) solidifying the unconsolidated web obtained by mechanical, hydromechanical, pneumatic and / or thermal methods known per se and / or by using chemical binders.

• viii) Zuführen von Fäden enthaltend Fasern oder Filamente aus nicht-schmelzspinnbaren Materialien, die aus einer Herstellungsanlage A' für diese Fäden stammen und Abziehen dieser Fäden durch mindestens eine Fördereinrichtung,
• i) gegebenenfalls Vorlage mehrerer Vorratseinrichtungen A mit Fäden, insbesondere mit Fäden enthaltend Fasern oder Filamente aus nicht-schmelzspinnbaren Materialien,
• ii) gegebenenfalls Vorlage weiterer Vorratseinrichtungen B mit Fäden, die sich von den in Vorratseinrichtungen A befindlichen Fäden unterscheiden,
• iii) gegebenenfalls Abziehen der Fäden von Vorratseinrichtungen A durch mindestens eine Fördereinrichtung,
• ix) statistisches Ablegen der in Schritt i) abgezogenen Fäden in Form eines ungebundenen Vlieses und in mehreren Schichten auf eine Transportvorrichtung,
• iv) statistisches Ablegen der in Schritt iii) abgezogenen Fäden in Form eines ungebundenen Vlieses und in mehreren Schichten auf eine Transportvorrichtung,
• v) gegebenenfalls Abziehen der Fäden von Vorratseinrichtungen B durch mindestens eine Fördereinrichtung,
• vi) gegebenenfalls statistisches Ablegen der in Schritt v) abgezogenen Fäden in Form eines ungebundenen Vlieses und in mehreren Schlichten auf eine Transportvorrichtung, und
• vii) Verfestigen des erhaltenen unverfestigten Vlieses durch an sich bekannte mechanische, hydromechanische, pneumatische und/oder thermische Verfahren und/oder durch Einsatz chemischer Binder.

In a further variant, the invention relates to a process for the production of nonwovens in which at least a portion of the filaments is fed directly from another production facility of the nonwoven forming installation. This procedure includes the measures:

• viii) feeding threads comprising fibers or filaments of non-melt-spun materials originating from a manufacturing plant A 'for these threads and removing these threads by at least one conveyor,
• i) if appropriate, provision of a plurality of supply devices A with threads, in particular with threads containing fibers or filaments of non-melt-spinnable materials,
• (ii) where appropriate, the provision of further stockpile arrangements B with yarns other than those in stocking equipment A,
• iii) optionally stripping the threads of supply means A by at least one conveyor,
• ix) statistically depositing the threads withdrawn in step i) in the form of an unbonded nonwoven and in a plurality of layers onto a transport device,
• iv) statistically depositing the threads withdrawn in step iii) in the form of an unbonded nonwoven and in a plurality of layers on a transport device,
• v) optionally withdrawing the threads of storage devices B by at least one För dereinrichtung,
• vi) optionally random depositing the strands withdrawn in step v) in the form of an unbonded nonwoven and in several sizing on a transport device, and
• vii) solidifying the unconsolidated web obtained by mechanical, hydromechanical, pneumatic and / or thermal methods known per se and / or by using chemical binders.

The execution The process can be carried out on a conventional spunbonding machine. In this case, the existing drafting devices are at least partially as conveyors or as pullers for The strings used from the storage facilities. These threads are in one or more upstream step (s) made and in the storage facilities introduced or directly from a manufacturing plant in the web formation plant brought in. These threads serve as a template for further processing in the spunbonding plant.

With the method according to the invention can be in addition to the nonwoven fabrics according to the invention described above also conventional Produce spunbonded nonwovens. Be the latter process variant in the storage facilities threads presented, which can be produced in the spunbond process fibers or Filaments exist. The web-forming process is carried out in such a way that Nonwovens with the desired Mass variation coefficients of the basis weight distribution CV become. in principle if one strives the filing of as possible many layers of as possible low basis weight at.

Prefers be with the inventive method produced the nonwoven fabrics according to the invention.

When Storage facilities can be used known devices, for example, coils or cans. The individual storage facilities A and B can contain the same or different threads.

When leave other production facilities A ' Use wet or dry spinning systems or plants for the Secondary spinning.

When Conveyors can be used known devices, in particular aerodynamically working devices, such as pneumatic conveyors.

Prefers become the threads from the storage facilities A and / or B or from the other manufacturing plant before entering the conveyors through thread guides passed at the entrance the conveyor are provided. This process variant allows the production of nonwovens with particularly low mass variation coefficient of the basis weight distribution CV.

The Storing the of the storage facilities A and B where appropriate or of the other manufacturing plant derived threads A, A 'and B as well as of optionally further filaments spun in the spunbonding machine C is done statistically in a known manner and not on one previously set storage point and on a locomotive Transport device, preferably on a storage belt, the openings if necessary can be distributed over several layers in multiple layers.

to statistical filing can the known deposition units are used. Examples for that are Deflection devices, which the thread bundles after leaving the mechanical conveyor distract and the course of each thread in a statistical way change. examples for Deflectors are baffles or other mechanical working ones Deflectors, aerodynamically operating devices or tubular collectors, which are longitudinal and / or move transversely to the movement of the transport device back and forth. The aim of these devices is an irregular filing of the threads to ensure the transport device.

To the Achieve high uniformity The strings stored in several layers on the transport device. The Number of layers is dependent of the desired productivity (= speed the transport device) so that the desired uniformity is obtained.

in the If the storage of the individual layers by deflectors one sets typically at least ten, preferably at least twelve of them to achieve the required number of individual layers.

in the If curtain curtain systems are used, it is best to use two, preferably four systems connected in series, to the required Number of individual layers to achieve.

Described is thus a continuous manufacturing process textile fabrics (also called nonwoven fabric here) such that mechanical, hydromechanical or pneumatic continuous, ie endless, thread-like solids of any origin, such as metallic, mineral, natural or synthetic, which are not processable by melt spinning optionally in Combination with filaments producible by melt spinning, statistically, ie not distributed to a previously directed depositing point, on a transport device, for example a traveling filing belt, in several layers one above the other and then the filamentary solids over these layers and the filamentary solids within a layer mechanically, hydromechanically, pneumatically, thermally or chemically connected to each other.

at The production of the nonwoven fabrics according to the invention can be the system technology a spunbonding system can be used.

there these may be installations where the spinning and drawing units are used the width of the entire product width corresponds (so-called curtain spinning systems).

It may also be plants in which spinning and drawing units single round spin packs, which are initially stretched filaments manufacture, which then with a transport system the storage belt supplied and with which the product width via this transport system is adjustable.

in the inventive method However, the part of the spunbonding, which is to melt and stretching thermoplastic polymers, not or only partly used. At least a part of the spunbonding plants provided stretching devices is used for feeding and transporting of already produced threads from storage facilities and / or other manufacturing facilities on the Transport device.

In a preferred embodiment the spunbonded system consists of an organ pipe-like Arrangement of pipes, respectively, the pneumatic transport of at least one endless thread (bundle) all the way over ensure continuously progressive storage belt, and from the tube outlet the statistical distribution of the threads through a longitudinal and randomly vibrating transversely to the running direction of the storage belt Transport pipe system, through a statistically longitudinal and transverse to the direction the storage belt vibrating filing system, or in that the Statistically statistical air between the pipe ends and the storage belt is moved takes place.

In a preferred variant of the method according to the invention takes place statistical filing of the threads by statistical movement of the storage units, by statistical Movement of the storage belt, by statistical movement of the air between Storage unit and storage belt or by a combination of two or three of these measures.

In a further preferred variant of the method according to the invention are the filaments deposited on the transport device through Air negative pressure (suction) on this detained.

Especially preferred is a method in which the threads A and / or A 'and optionally the Threads B additionally Filaments C are deposited in the same plant by melt spinning made of filament-forming materials and that after passing a drawing device together with the threads A and / or A 'and optionally the threads B are stored on the transport device.

A Another preferred variant of the method according to the invention comprises Production of filaments C in the spunbonding machine, the multicomponent filaments of at least two incompatible, fissile, melt-spinnable and fiber-forming polymers, and splitting these multicomponent filaments in step vii) by water jet treatment.

To the filing of the threads on the transport device, these become one or in succession fed to several solidification steps.

The Solidification of the resulting unconsolidated web can by known mechanical, hydromechanical, pneumatic and / or thermal Process and / or by using chemical binders.

Examples for that are the use of needle chairs, of fluid or air jets, calendars or thermally crosslinking Binders or binding fibers and self-crosslinking binders. It can too Combinations of these methods are used.

The preferred solidification technique in the production of the nonwovens of the invention is the solidification through the use of water jets.

The nonwovens of the invention can be used in a wide variety of fields. Examples are textile and in particular technical applications. The nonwovens of the invention can be used in applications that are today reserved for fabrics or other fabrics. Examples of these are the use as textiles, such as clothing fabrics, home textiles or industrial textiles, or the use as technical fabrics, in particular as high-strength materials for use as a textile fabric for architectural applications, or the use as a carrier for coated or impregnated nonwovens, or for use in the filtration of fluid streams or liquids.

These Uses are also the subject of the present invention.

The Nonwovens described herein could be used in Fuel cells are used, which from chemical energy sources electrical Generate energy. From the literature, for example, hydrogen-oxygen fuel cells known. In fuel cells, membranes are between electrodes arranged. These membranes can so-called gas diffusion layers are assigned, which are the membranes preferably should not damage. The Nonwovens described herein are particularly suitable as gas diffusion layers or as parts of gas diffusion layers, since almost not the danger the membranes are damaged by fiber ends of the nonwovens. This depends with the structural composition of nonwovens composed of filaments or Endless fibers are constructed. This structure shows not only high stability but also a surface structure with few fiber ends.

The explain the following examples to limit the invention without this.

example 1

10 Cops (spinning bobbins) viscose filament yarn from ENKA, type 84f31 untwisted with a single filament denier of 2,7dtex were added hung from a board provided with holders, from there over the narrow side of the conical cop in a normally in one Spunbonding machine as drawing unit of freshly spun filaments serving Venturi nozzle passed and pneumatically withdrawn from the cops. The yarns were directed into a pipe system, which passes into a so-called traveler system, which consists of a telescopically telescoping tube on the end of a simultaneously in the machine direction and transverse to the machine direction swinging head statistically points out the emerging filaments distributed in the machine direction tray.

at one for the stretching of freshly spun polyester filament typical Pressure of 3.2 bar at about 3000m / min was about 200g / min Viscose Filament in a homogeneous but dissymmetrical spot of about 500 mm diameter be stored on the storage belt.

The loose batt was sprayed with a wood glue diluted at 1:30 with water (Ponal, Henkel), the water evaporated at a calendering step, which in a first step was preliminarily pre-consolidated by means of a needle-wheel (slightly splitting off the spray-glue batches), and in a second step with four water jet passages à 230 bar and about 10 m / min finally solidified to a Viskoseendlosfilamentvliesstoff. A basis weight of 122 g / m ² with a mass variation coefficient CV of 7.5 was obtained.

Example 2

Analogous Example 1, 10 cops viscose filament yarn Fa. ENKA, Type 84f60 untwisted with a single filament titer of 1.4dtex into the draw unit of the spunbond test facility described in Example 1 fed. It was filed a spot of about 55cm diameter, at a throughput of about 220g / min and a spinning station. Now The Traveler system was turned on, and the storage width so set to the depositing belt speed that the deposited spot, the moving in a zigzag form across the advancing storage belt, mostly overlapped.

As a chemical bond, commercial wood glue 1:30 was diluted with water, sprayed with a hand spray (flower syringe) evenly on the slowly progressing batt and evaporated the solvent (water) in the heated calender. The easily adhered viscose filament yarns thus obtained were fed to a needle-punch and pre-consolidated at about 60 punctures per cm ² so that the fabric could be rolled up.

The product was unrolled before a hydroentanglement plant, fed to this plant and there hydroentangled at 4 × 230 bar at about 10 m / min and then dried in a floating dryer. An approximately 40 cm wide, non-thermoplastic nonwoven fabric having a basis weight of 115 g / m ² with a mass variation coefficient CV of 6.1% was obtained.

Example 3

Analogously to example 1, 10 cops viscose filament yarn from ENKA, type 167f42, were fed untwisted with a single filament denier of 3.9 dtex into the draw unit of the spunbond test facility described in example 1. At about 200 m / min transport speed, a throughput of 330 g / min and a spot of about 45 cm could be obtained. A basis weight of 152 g / m ² with a mass variation coefficient CV of 8.2% was obtained.

Example 4

Analogously to example 3, 10 cops viscose filament yarns from ENKA, type 84f60 were fed untwisted into the drawing unit of the spunbonded nonwoven plant described in example 1. A spot with a basis weight of 234 g / m ² with a mass variation coefficient CV of 9.8% was obtained.

Example 5

In one described in EP-A-814,188 and for the preparation of Microfilament spunbonded web spunbonded webs into the drafting units, i. into the venturi, during the ongoing process for drawing freshly spun, in the drawing step befindlicher Polyester-polyamide bicomponent filaments at a spinning speed of about 4,500m / min, each a Viskosefilamentgarn example 3 supplied, filed with, and incorporated by hydroentanglement, while the Bicomponent filaments were split and solidified. Surprisingly here at about 3.5 bar drawing air pressure and the much higher spinning speed opposite the biko filaments the viscose filament yarn speeds described in Example 1-1 from 1500 m / min no disturbances detected. There were neither congestion within about 7-10 m long Travelersystems (telescoping tubes) still knots stopped at the filing. So could a much improved specific tear propagation resistance of the microfilament nonwoven fabric.

Example 6

In Further experiments analogous to the implementation of Example 5 were FOY-PET multifilament yarns the company SETILA, filament type 100f88 to the freshly woven, added in the drawing phase bicomponent filaments and the solidification conditions selected such that again good piling resistances were achieved. Due to the added multifilament yarns could the tear strength the obtained area goods be increased enormously. Although the bicomponent filaments with the for typical process speeds of 4500 m / min in the pipe system moved, and at the same time a Abspulgeschwindigkeit of contrast, only 1500m / min reached, there were no disturbances in the process. simultaneously could very good basis weight uniformities be achieved.

The nonwovens produced had the following characteristics:
Basis weights of 100 to 107 g / m ² : CV values of 5.2 to 7.2%
Basis weights from 127 to 133 g / m ² : CV values of 5.2-6.4%
Basis weights from 164 to 168 g / m ² : CV values of 4.8-5.4%

Example 7

The Procedure of Example 5 was repeated. There viscose a other coloring when polyester and polyamide are needed, the test was carried out with a polyester filament yarn made of high-strength (POY) polyester (polyethylene terephthalate = PET). For this purpose, in the spunbonded web plant described in Example 5 the stretching units, i. into the venturi, during the ongoing process for drawing freshly spun, in the drawing step befindlicher Polyester-polyamide bicomponent filaments at a spinning speed of about 4,500m / min, one each POY-PET filament yarn from the company SETILA, article 12058, type 100f88 fed with a single filament denier of 1.14dtex, with filed, and incorporated by hydroentanglement while the bicomponent filaments split and solidified.

Example 8

In a curtain spunbonded pilot plant with a rectangular construction (Spinpack over the entire width of the plant) was the melt spinning content of Plant not activated.

through second coil stand for each Twenty filament bobbins were placed on a 40 by means of a comb-like device Width of 80 cm at even spacing held polyurethane filament yarns from. Elastogran, type Elastollan IREL 22 dtex from one broadside into the rectangular tertiary air channel guided and supplied to the storage belt.

A basis weight of 100 g / m ² with a mass variation coefficient CV of 6% was obtained.

Claims (30)

Nonwoven fabric having a basis weight of up to 250 g / m ² and having a high uniformity, expressed by a mass variation coefficient of the basis weight distribution CV of less than 10% as determined on 5 x 5 cm ² samples of randomly deposited non-spun yarns Contains threads. Nonwoven containing randomly deposited threads non-melt- Materials. Nonwoven fabric according to claim 1 or 2, characterized that of these threads made of fibers or filaments. Nonwoven fabric according to one of claims 1 to 3, characterized that this is a uniformity, expressed by a mass variation coefficient of the basis weight distribution CV of smaller than 7%. Nonwoven fabric according to one of claims 1 to 4, characterized that of these threads made of high-strength plastic fibers or high-strength plastic filaments, having. Nonwoven fabric according to one of Claims 1 to 5, characterized that of these threads made of metal or metal alloys. Nonwoven fabric according to one of claims 1 to 6, characterized that of these threads of additized plastics, preferably of spun-dyed and / or flame-retardant Plastics, has. Nonwoven fabric according to one of claims 1 to 7, characterized that in addition statistically deposited and spunbonded filaments having. Nonwoven fabric according to claim 8, characterized that it is the filaments produced in the spunbond process is split filaments, that of multicomponent filaments containing at least two incompatible, fissile, melt spinnable and fiber-forming polymers are derived, in particular Spaltfilamente from the combination polyester / polyamide, polyester / polyolefin, polyamide / polyolefin, Polyolefin / polyolefin, polyester / polyurethane, polyamide / polyurethane or polyolefin / polyurethane. Nonwoven fabric according to claim 2, characterized that this exclusively filaments and / or non-melt-spun fiber yarns fiber-forming materials. Nonwoven fabric according to claim 2 or 10, characterized that the non-melt spinnable material is selected from the group consisting of Cotton, wool, cellulose and cellulose derivatives, in particular Viscose, modal, copper silk, cellulose acetates, hemiacetals or triacetates, made of polyacrylonitrile, aromatic polyamides (aramids), non-thermoplastic Polyurethanes, non-melt-spinnable halogenated polyolefins, in particular polytetrafluoroethylene, polyvinyl chloride or polyvinylidene chloride, as well as rubbers, polyvinyl alcohol or carbon. Nonwoven fabric according to claim 2 or 10, characterized that the non-melt spinnable material is a fiber-forming polymer is or by peeling process is spinnable polymer. Nonwoven fabric according to claim 8, characterized that the filaments produced in the spunbond process are derived melt-spinnable thermoplastic polycondensates selected from the group consisting of polyesters, polyamides, polyether ketones, Polyarylene sulfides, Polyarylenethersulfonen, polycarbonates, proteins and Protein derivatives, or derived from melt-spinnable thermoplastic Polymers as selected are selected from the group consisting of polyolefins and polyurethanes, or derived from other melt-spinnable materials, the selected are made of the group consisting of metals and glass or combinations of two or more of these polycondensates, polymers or other materials. Nonwoven fabric according to one of claims 1 to 13, characterized that this through the use of mechanical, hydromechanical and / or thermal processes, in particular through the use of needle chairs or of water jets, has been solidified. Process for producing nonwovens comprising the measures: i) Template of several storage devices A containing threads, in particular with threads Fibers or filaments of non-melt spinnable materials, ii) if appropriate, further supply devices B with threads, the differ from the threads in stock A, iii) Pulling off the threads of storage devices A by at least one conveyor, iv) statistical deposition of the strands withdrawn in step iii) in the form an unbonded web and in multiple layers on a transport device, v) optionally stripping the threads of storage devices B by at least one conveyor, vi) if applicable, statistical storage of the deducted in step v) Threads in Form of an unbonded fleece and in several layers on one Transport device, and vii) solidifying the resulting unconsolidated Fleece by mechanical, hydromechanical, pneumatic and / or thermal processes and / or by using chemical binders. A process for the production of nonwovens comprising the measures: viii) feeding threads comprising fibers or filaments of non-melt spinnable materials originating from a manufacturing plant A 'for these threads and stripping these threads by at least one conveyor, i) optionally presenting a plurality of storage devices A. with threads, in particular with threads containing fibers or filaments of non-melt-spinnable materials, ii) optionally presenting further supply means B with threads other than the threads located in supply means A, iii) optionally stripping the threads of supply means A by at least one conveyor, x) statistically depositing the threads withdrawn in step i) in the form of an unbonded one Fleece and in several layers on a transport device, iv) random depositing the strands withdrawn in step iii) in the form of an unbonded nonwoven and in several layers on a transport device, v) optionally stripping the threads of storage devices B by at least one conveyor, vi) optionally statistically depositing the threads withdrawn in step v) in the form of an unbonded nonwoven and in several layers on a transport device, and vii) solidifying the unconsolidated nonwoven fabric obtained by mechanical, hydromechanical, pneumatic and / or thermal methods and / or by Use of chemical binders. Method according to claim 15 or 16, characterized that coils or cans are used as storage devices. Method according to claim 16, characterized in that that as other manufacturing plants A 'wet or dry spinning or Facilities for the secondary spinning be used. Method according to one of claims 15 to 18, characterized that as conveyors pneumatic conveyors be used. Method according to one of claims 15 to 19, characterized that the threads from the storage facilities A and / or B and / or from the other Manufacturing plant A 'before entrance to the conveyors through thread guides be passed, which at the inlet opening of the conveyors are provided. Method according to one of claims 15 to 20, characterized that this is carried out on spunbonded systems in which the spinning and drawing units are arranged along the entire product width. Method according to one of claims 15 to 21, characterized that this is carried out on spunbonded systems, where as spinning and drawing units single round spinpacks for the production of stretched filaments are provided, and having a transport system, with the the filaments are fed to a storage belt, the product width over the Transport system is adjustable. Method according to one of claims 15 to 22, characterized that the filing of the threads A and / or the threads A 'and, where appropriate, the Threads B statistically and not to a predetermined storage location and on a moving storage tape in several layers one above the other distributed. Method according to one of claims 15 to 23, characterized that in addition to the threads A and / or the threads A 'and optionally the Threads B Filaments C are deposited in the same plant by melt spinning made of filament-forming materials and that after passing a drawing device together with the threads A and / or the threads A 'and optionally the threads B are stored on the transport device. Method according to Claim 24, characterized that the filaments C multi-component filaments of at least two incompatible, fissile, melt spinnable and fiber-forming polymers used in step vii) by water jet treatment be split. Method according to one of claims 15 to 25, characterized that the statistical filing of the threads through statistical movement the depositing units, by statistical movement of the storage belt, by statistical movement of air between storage unit and Filing tape or by a combination of two or three of these Activities. Method according to one of claims 15 to 26, characterized that deposited on the transport device threads through Air negative pressure (suction) can be recorded on this. Method according to one of claims 15 to 27, characterized that the solidification by the use of water jets takes place. Use of the nonwovens according to one of claims 1 to 14 as textiles, as clothing fabrics, as home textiles or as industrial textiles, as technical fabrics or as a carrier for coated or impregnated Nonwovens, or in the filtration of fluid streams or liquids. Use of a nonwoven fabric according to one of claims 1 to 14 in a fuel cell.