Non-woven fabric

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Random nonwoven fabric of a cleaning rag under the microscope

A nonwoven ( English nonwoven ; French nontissé ; Russian нетканый материал ) is a structure of fibers of limited length, continuous fibers ( filaments ) or cut yarns of any kind and of any origin, which are in some way combined to form a nonwoven (a fiber layer, a fiber pile ) have been linked in some way; excluded from the interlacing or entanglement of yarns as the weaving , knitting , knitting , the lace making , the lichen and manufacture of tufted done products. Nonwovens do not include foils and papers .

Nonwovens are for the most part flexible textile fabrics, ie they are easily bendable, their main structural elements are textile fibers and they have a comparatively small thickness compared to their length and width. However, nonwovens are also produced with a relatively large thickness, which must be assigned to spatial structures (e.g. nonwovens for insulation and cushioning materials). There are also nonwovens that are more similar to papers, foils or fiber-reinforced plastics than textiles because of the fibers used (e.g. short fibers that cannot be spun) or the consolidation process .

Nonwovens represent a material group with a wide range of properties that can be specifically adapted to a wide range of application requirements due to the large number of usable raw materials and manufacturing variants.


The definition of nonwovens has been subject to constant changes resulting from the rapid development of manufacturing processes on the one hand, and adaptations to international standards and definitions of international organizations in the nonwovens industry, such as EDANA (founded in 1971 as the European Disposables and Nonwovens Association) and INDA ( founded in 1968 as the International Nonwoven and Disposable Association). In particular, the delimitation from traditional products of the textile industry (such as felt ) or papers have an influence on the definition.

The word fleece (formerly also fleece, from Latin vellus "wool", "sheepskin") is first used in German in the 16th century in connection with the golden fleece . In the field of sheep breeding, it generally refers to the coat of the sheep, in particular the shorn, cohesive wool blanket. Since the 19th century, the term has generally been used to describe a flat structure that consists mostly of individual fibers, the cohesion of which is essentially only given by their own adhesion. Initially it was produced exclusively on cards or cards , which were mainly used in the course of yarn production for fiber preparation. Such nonwovens made of staple fibers were and still are the preliminary product for wadding , felt and nonwovens. Later on, flat structures made from filaments (continuous fibers) deposited directly after the polymer melts or solutions, from short fibers or from split foils as fleeces were added, which are mainly described by the term “web” in English.

The patent specification No. 1062206 of the Federal Republic of Germany with the title: “Process for the production of nonwovens”, which was registered in 1952, can be seen as a starting point for the use of the term “nonwovens” . It can be seen from this that the end products produced by applying film-forming adhesives based on aqueous dispersions to nonwovens made of synthetic and natural fibers and then drying them at elevated temperature are nonwovens. Previously, the fiber fleeces bonded by means of binders were referred to as impregnated fiber-like fabrics, synthetic leather-like flat structures or rubberized fiber-containing flat structures. The nonwovens consolidated by needling as needle felts .

Despite this distinction made since the early 1950s between the preliminary and intermediate product “nonwoven” and the end product “nonwoven”, nonwovens are often referred to as nonwovens in a shortened way.

In the 1940s and especially from the 1950s onwards, the term "nonwoven" was introduced in the USA for a product based on a solidified fleece, and for the new product group "nowoven fabrics" (nonwoven textiles), which was followed by a detailed discussion of the Nonwovens Subcommittee of the American Society for Testing and Materials (ASTM) and the American Association of Textile Chemists Colorists, in which no more suitable term was found. Although this term linguistically only expresses a differentiation from woven fabrics, it was intended to distinguish it from all conventionally manufactured flat textiles, including knitted and crocheted fabrics, and despite this controversial representation method established itself in the international professional world. In this way it became the starting point for definitions in French, Russian and other languages.

The term "bonded fiber fabrics", used especially in Great Britain at the time, for nonwovens was later dropped in the English-language specialist literature . On the other hand, especially in German and Austrian research and teaching institutions (e.g. by Kurt Meyer, Peter Böttcher, Helmut Jörder and Hermann Kirchenberger) from the end of the 1950s to the 1970s due to the fact that especially in the Comecon countries, in addition to the nonwovens Rapidly emerging new fabrics using threads (e.g. Malimo) and combinations of different textile fabrics created a reorganization on the basis of the textile structural elements used in these new textile fabrics under the generic term “textile composites”. In addition to the terms “thread composites” and “layered composites”, the term “fiber composites” has also been proposed, which should be used as a synonym for nonwovens. This view was espoused by Radko Krčma in particular at this time and worked out into a detailed system.

Ultimately, these considerations did not prevail, since the term nonwovens has meanwhile been used in industry and business and has been used specifically in numerous patent specifications that reflect the state of the art. From the end of the 1960s, as part of the German set of standards, a separate standard was created within the textile standards for nonwovens, after already in DIN 60 000: 1969, which has the basic terms of textiles as its content, nonwovens briefly as flexible flat structures that are made by solidifying Nonwovens are produced, have been defined. In this new DIN 61 210: 1970 with the title “Nonwovens - Nonwovens - Technological Classification” it was expressly noted that this should enable a distinction to be made between “classic” textile products and the textile products made according to these newer processes.

This standard DIN 61 210 was replaced in 1982 by a significantly expanded and revised edition entitled Nonwovens, consolidated nonwovens (felts, nonwovens, wadding) and nonwoven composites based on textile fibers - technological classification . Although this standard was withdrawn without replacement in 2007, it forms the basic framework for the subdivision of nonwovens according to manufacturing process in German-speaking countries. The content essentially corresponds to ISO standard 11 224 with the title “Textiles - Web formation and bonding in nonwovens - Vocabulary”, which has existed since 1993, or its 2nd edition from 2003.

A further clarification of the definition of the term “nonwoven” and its differentiation from other flat structures was made with DIN 61 210, Part 2 in 1988, whereby the focus here was on the differentiation from paper. The nonwoven fabric was defined as a flat structure which consists entirely or to a substantial extent of fibers, whereby these can be staple fibers or filaments (continuous fibers) and / or fibers with a degree of slenderness (ratio of fiber length in mm to fiber diameter in mm) of at least 300 . The type of interconnection of the fibers in the nonwoven is the form fit (by entanglement) and / or the cohesion and / or the adhesion, whereby the character-determining fibers in the nonwoven can be oriented or randomly arranged.

As an essential distinction to papers, which also mainly consist of fibers, it was determined that with a proportion between 30% and 50% of the fibers, which determine the nonwoven character, and the remaining fiber proportion consists of paper-like pulp, the bulk density is below 0.40 g / cm³ must be in order to assign it to the nonwovens. If the fiber content determining the nonwoven character is less than 30%, regardless of the bulk density, the product is not counted as nonwovens. Despite this demarcation, it happens again and again that products that are manufactured according to the wet nonwoven process, which is similar to the paper production process, are sometimes referred to as nonwovens and sometimes as long-fiber special papers.

A differentiation from wadding and felts, which are also based on nonwovens, is also made in this standard DIN 61 210-2. The products made up of layers of nonwovens are classified as nonwovens and not as wadding if there is not only a superficial but also an extensive consolidation on the inside or if preferably only the layer close to the surface is completely and evenly consolidated and smoothed. For the distinction between felts and nonwovens, reference is made to DIN 61 205 (withdrawn in 2006 without replacement), in which the necessary use of feltable fibers to differentiate between felt and needled felt (needle felt) or needled nonwoven (needle felt) is mentioned in the former becomes. A distinction between needle felt and needle felt is based on the density . Products with a density <0.15 g / cm³ are then counted as nonwovens, all with the same or higher density as needle felts.

This distinction between needle felt and needle felt was no longer made in the successor standard DIN EN 29 092: 1992. Only felts produced by wet rolling were excluded from the nonwovens. The latest standard DIN EN ISO 9092, which is valid for the definition of nonwovens and is essentially described in the introduction to this article, goes even further. There, felts are no longer explicitly separated from the nonwovens. All comments from the previous standard from 1992 have been deleted. Only paper and foils were excluded from the “nonwovens” alongside classic yarn-based textiles. The standard no longer contains a description of the characteristics on the basis of which a distinction can be made between paper and nonwovens. In the preface it is pointed out that patent rights may be affected by texts in this document.

Since the standards mentioned are not legally binding but are only recommendations, other classifications under the term nonwovens are also possible. For example, the definitions and classification principles of the international nomenclature of use, the harmonized system (HS), differ from the main criteria of the above mentioned standard.


A subdivision of the nonwovens can be made according to very different criteria and therefore leads to a large number of product names for nonwovens and solidified nonwovens, the nonwovens. Often there are different designations for the same products, which have emerged over the years from new approaches or from newly added processes or raw materials. If necessary, this is indicated below. The following statements are based on standard works on nonwovens, as specified in the individual references or the literature references, the earlier DIN 61 210: 1982 and ISO 11 224: 2003.

Subdivision according to the type of fiber

A fundamental distinction between fibers is made in

  • Natural fibers (vegetable fibers, animal fibers and inorganic fibers) and
  • Man-made fibers made from natural polymers, from synthetic polymers and from non-polymers

Accordingly, one subdivides into natural fiber and chemical fiber nonwovens.

As rough estimates of the suitability of the nonwovens for use in terms of chemical, thermal and physical textile behavior can be derived from the specification of the type of fiber used, a more detailed classification (naming) is often made.

So with nonwovens made of:

Information about fiber blends is common for nonwovens (e.g. viscose / polyester fiber nonwovens).

Division according to the fiber length

A subdivision can be made into staple fiber nonwovens, usually only referred to as fiber nonwovens, and continuous fiber nonwovens (filament nonwovens). The common name for the nonwoven fabric made from fibers of practically unlimited length is spunbonded nonwoven fabric.

Subdivision according to fiber fineness

There is no exact definition of the classification of nonwovens or nonwovens based on the fineness of the fibers used to form the nonwoven. Nonetheless, nonwovens are named in connection with denominations of fineness, especially in the case of nonwovens for filtration and barrier layer applications, as a certain pre-selection for their suitability can be estimated. The smaller the fiber diameter in micrometers (µm) or nanometers (nm) or the length-related mass in tex or dtex, the closer the fibers are in the nonwoven with the same mass per unit area . The pore size of the filter nonwoven is reduced.

The designation fine fiber nonwoven (also fine fiber nonwoven) or microfiber nonwoven is mostly used for a nonwoven in which the fibers have a diameter between one and ten micrometers (µm) or 0.1 and 1 dtex. Nonwovens in which the fibers have a diameter of less than 1 µm (1000 nm) are often referred to as nanofiber nonwovens. There are also proposals to designate these as nanofiber nonwovens only for fiber diameters below 500 nm or below 300 nm, since in other technical areas only those with a diameter below 100 nm are counted among the nanostructure elements. Most of these nonwovens or nonwovens in the nano range do not have fibers with a certain diameter, but a mixture with different diameters.

Subdivision according to fiber orientation

According to the orientation of the fibers in the non-woven fabric, which is ultimately roughly found in the non-woven fabric, one differentiates:

  • Oriented nonwovens or nonwovens in which the fibers are very strongly oriented in one direction. In the case of longitudinal nonwovens or longitudinal nonwovens (longitudinally laid nonwovens or nonwovens), the majority of the fibers then lie in the longitudinal direction of the nonwoven produced (in the machine direction of the production line, in English "machine direction" - MD). In the case of cross-wovens or cross-wovens (cross-wovens or nonwovens), the majority of the fibers lie in the cross direction (CD). This MD / CD ratio is used very often to characterize nonwovens.
  • Cross-layer nonwovens or nonwovens, in which the fibers are preferably oriented in two directions by superimposing individual fiber batts or nonwovens with a longitudinal orientation of the fibers to the overall nonwoven by means of cross-layers.
  • Random nonwovens or random nonwovens (often also referred to as random nonwovens or random nonwovens), in which the staple fibers or filaments can take any direction, d. H. present relatively evenly distributed in all directions of the nonwoven fabric.

Random nonwovens are also referred to as isotropic nonwovens, while oriented nonwovens are anisotropic nonwovens. This is particularly reflected in the isotropic or anisotropic mechanical behavior of the nonwovens.

Subdivision according to the manufacturing process

The division according to the manufacturing process is most often used to represent the field of nonwovens. There is a further breakdown into the processes of web formation and web consolidation. In the manufacture of nonwovens, combinations of nonwoven formation and combinations of nonwoven bonding are used more and more frequently. A uniform system for the nonwoven and nonwoven manufacturing processes and the name derived from this for nonwovens and nonwovens has not yet established itself.

Fleece formation

A subdivision of the processes of web formation can be made according to DIN 61 210 as follows:

  • Mechanically formed nonwovens are those which are formed from piles removed from cards or cards, which are laid on top of one another to form nonwovens, or are formed directly by these carding machines. These are generally fleeces made from staple fibers. The terms carded fleece or dry fleece exist for these fleeces, as they are produced in a dry way. Depending on the type of filing of the fleeces, oriented fleeces or cross-ply fleeces are created, and when using special cards, tangled fleeces are created.
  • As aerodynamically formed such webs are referred to, which are formed from fibers by means of an air stream on an air-permeable base.
    • If the fleeces are made from staple fibers or short- cut fibers and flock pulp , they are referred to as dry fleeces. There are generally randomized nonwovens and, after appropriate consolidation, dry nonwovens or randomized nonwovens.
    • If nonwovens are formed from fibers that are spun directly from polymer melts passing through nozzles and stretched until they are torn by means of hot air currents, so-called meltblown nonwovens are created. They usually consist of longer staple fiber-like continuous fiber sections, but also of a mixture with continuous fibers or completely of continuous fibers. The solidified nonwovens that build on it are usually referred to as meltblown nonwovens.
    • If nonwovens are formed from fibers that are spun from polymer melts passing through nozzles and stretched by means of cold air and / or mechanically, by direct laying down, they are referred to as spunbonded fabrics or, after consolidation, as spunbonded nonwovens. The terms spunlaid nonwovens or, for the consolidated nonwovens, spunlaid or spunbonded nonwovens in use. The fleeces are built up exclusively from filaments or continuous fibers.
    • Because of the low strength of the individual fibers, meltblown nonwovens are often only produced in layers with spunbonded nonwovens, for example spunbonded meltblown nonwovens (SMS), which form the basis for the so-called SMS nonwovens.
  • As a hydrodynamically formed such webs are referred to, in which the fibers are suspended in water and are deposited on a water-permeable base. If shorter staple fibers, but also flock pulp, are used, the fleeces are referred to as wet fleeces. The subsequently consolidated nonwovens as wet nonwovens. The process is also often referred to as the wet process. If continuous fibers, which are spun directly from polymer solutions, optionally drawn, are laid down to form a fleece by means of water, wet spunbonded nonwovens or, in solidified form, wet spunbonded nonwovens are obtained.
  • Electrostatically formed fleeces are those whose fibers are formed and deposited from polymer solutions or melts under the action of an electric field. So-called fine fiber fleeces or nanofiber fleeces are produced.

Another, very frequently used subdivision of the nonwoven forming processes is that of the dry process, wet process and extrusion process .

Only the mechanical and aerodynamic web-forming processes based on staple fibers are assigned to the dry process, and the hydrodynamic web-forming process based on staple fibers is assigned to the wet process. Initially, only those extrusion processes for fleece formation were assigned that were based on polymer melts, i.e. the formation of the melt-blown (meltblown) nonwovens and spunbonded nonwovens from continuous fibers, the formation of ultra-fine nonwovens by electrospinning and of film fiber nonwovens, which are Fibrillation of extruded films can be produced. In more recent systematics, extrusion webs are also assigned to those in which a web is formed from fibers formed directly from polymer solutions by the electrostatic spinning process or the so-called flash spinning process ( relaxation evaporation spunbonding process).

A schematic representation of the web formation process, such as drylaid nonwovens using both the mechanical (carded) and aerodynamic (airlaid) processes, nonwovens from the polymer melt (spunbonded nonwovens, spunmelt) and wetlaid nonwovens to be found on the homepage of the international nonwovens organization EDANA.

Web consolidation

The methods of web consolidation, i.e. H. The conversion of a nonwoven into a nonwoven by creating a stronger bond between the fibers than is present in the nonwoven are usually divided into mechanical, chemical and thermal.

  • In mechanical bonding processes, the fibers are bonded by frictional engagement or a combination of frictional and positive engagement .
    • With the frictional connection, the distance between the neighboring fibers is reduced compared to that in the fleece by compressing the fleece. This increases the adhesion of the fibers to one another and higher forces can be transmitted. The resistance of the fleece to deformation increases , it becomes stronger. The compression can be achieved by shrinking all fibers or a portion if the fibers are shrinkable when exposed to heat and / or a swelling agent. Shrink nonwovens or swellable nonwovens are produced. Compaction can also be done by pressing (mostly calendering) or by milling, in which the fibers of the fleece must be capable of being felted and felted together by simultaneous thermal, chemical and mechanical effects. By walking arise felts or Walk nonwovens.
    • In the case of the nonwovens produced by a combination of friction and form-locking bonds, the fibers of the nonwoven are intertwined with one another by mechanical effects.
      • This entangling of the fibers and thus the compression and consolidation of the fleece can be done by needling, in which a large number of special needles (barb needles, fork needles) arranged in a needle board or bar are pierced and cut out. Needle nonwovens are produced. This type of consolidation can be used for webs made from staple fibers or continuous fibers.
      • When using compound needles to pierce the fleece, tufts of fibers can be "intermeshed". H. they take on loop-shaped arrangements ("meshes"). Cross-layer nonwovens made of staple fibers are used for this. The fiber nonwoven knitting process creates nonwovens such as Malivlies.
      • The intertwining of the fibers can also be done by swirling by z. B. focused high pressure water jets act on a fleece that is guided over a liquid-permeable base. This creates so-called hydroentangled nonwovens (also known as vortex nonwovens, spunlaced nonwovens or hydroentangled nonwovens). Oriented nonwovens or random fiber nonwovens made of staple fibers (also with the addition of flock cellulose), but also spunbonded nonwovens are consolidated using this principle.
  • In the chemical consolidation process, the bond between the fibers is created through a bond using additives. The connection of the fibers by means of additives, so-called binders , is also known as adhesive bonding. In the majority of chemical processes, the binder is applied in liquid form (e.g. polymer dispersions ) to the fiber fleece and hardened by a subsequent heat treatment ( drying , condensation , polymerization ), which solidifies the fleece. The liquid binder can be applied by impregnation (e.g. using a padder ), by spraying, patting or squeegeeing or printing . These processes can be used to consolidate all types of nonwovens. They are generally referred to as adhesively bonded nonwovens or binder-bonded (binder-bonded) nonwovens or, in more detail, depending on the type of application, e.g. B. referred to as spray nonwovens or binder-printed nonwovens. The proportion of the binder in relation to the fiber mass of the fleece can be between 5% (slight surface consolidation) and up to 150% (e.g. shoe stiffening nonwovens). All types of nonwovens are consolidated with these methods.
  • Chemical processes with material bonding can also include those in which the solid binders or the main fiber component on the surface are temporarily dissolved or loosened by the action of solvents and after the evaporation or evaporation of the solvent with the fibers or connect the fibers to each other. Fiber nonwovens are created.
  • In the thermal consolidation process, the bond between the fibers is also established through a material bond, whereby a distinction is often made between adhesive and cohesive bond. Requirements are additional thermoplastic components or thermoplastic fibers.
    • In adhesive bonding, binders are added to the fleece in solid form as fibers or powder. In fiber form, separate "binding fibers" can already be added during the web formation process, such as low-melting spun fibers in fiber webs or the addition of elementary threads from a variant with a lower melting temperature compared to the main fiber component (e.g. with some polyester spunbonded nonwovens made of two different polyesters ) or the web entirely are formed from bicomponent fibers, of which the low-melting component acts as a binder. The thermoplastic binder is obtained by a thermal treatment, e.g. B. by hot air flow (thermofusion) or thermocalendering by means of engraved and / or smooth rollers, in which pressure acts at the same time in addition to the heat, brought into a sticky-liquid state, so that it can surround the main fiber components and create a solid connection after cooling . Ultrasonic welding is also used , which creates very well localized softening of the thermoplastic fibers in the nonwoven and thus local solidification points in the nonwoven. This thermal process consolidates both nonwovens (by means of thermofusion nonwovens up to mass per unit area of ​​4000 g / m²) and spunbonded nonwovens, if they have the appropriate adhesive components. It can also be used to solidify nonwovens made of natural or non-thermoplastic man-made fibers if thermoplastic components are mixed in.
    • In cohesive bonding, thermoplastic fibers of the same raw material are bonded to one another without an additional binder. The fibers are welded together, in which they soften through the temporary action of elevated temperatures and the neighboring fibers connect at the points of contact. Very often the connection is made with simultaneous application of pressure. In particular, light fiber fleeces and light spunbonded nonwovens are consolidated in this way by heated embossing calenders, but also by ultrasonic welding systems.

A schematic representation of some web bonding processes, such as chemical bonding by means of liquid binders, thermal bonding with calender (thermal bonding, calendering) or mechanical bonding by needling (mechanical bonding, needle punching), is on the homepage the international nonwovens organization EDANA.

Subdivision according to the arrangement of the binding sites

  • Continuously consolidated nonwovens are those in which the binding points are evenly distributed over the length, width and thickness. In the case of many nonwovens, the aim is for binding points to be arranged as far as possible at the intersection of the fibers (so-called binding sails), although this is not always possible when primarily liquid binders are added. Under certain drying conditions, the migration of the binder forms a type of porous binder film on the surface of the nonwoven.
  • Locally consolidated nonwovens are those in which the fibers are connected locally according to a type of pattern. For this purpose z. B. embossing calenders, ultrasonic systems or methods of binder printing can be used. The nonwovens produced in this way are called embossed nonwovens or binder-printed nonwovens.
  • Superficially consolidated nonwovens are those in which only the fibers of the layers close to the surface are specifically bonded with the binder. Nonwovens of this type of consolidation are referred to as spray nonwovens.


Due to the large number of raw materials that can be used (fibers, binders, additives), the numerous manufacturing processes and their combinations, as well as additional finishing processes and the associated wide range of properties, nonwovens represent a material group with a wide range of possible uses. Often, their use is not for the consumer and user of products immediately visible as they are included in complex product designs. Allocation to specific application areas (market segments) is not always handled in a uniform manner. Examples of applications for nonwovens are given below. T. the application designation of the nonwoven, z. Sometimes only the product is mentioned in which one or more types of nonwoven are used. Some selected application examples are given below. A comprehensive presentation with a detailed description of the types of nonwovens and the properties required for their application can be found in the literature.

Nonwovens for hygiene products

Nonwovens for personal care products

Nonwovens for medical devices

Nonwovens for cleaning products in the household and contract sector

Nonwovens for home furnishing

Non-woven fabrics for clothing

Nonwovens for technical applications



vehicle construction

  • as a decorative material and to stabilize and cover the foam core in the headliner construction
  • Barrier layer between decorative material and plastic when molding trim parts (e.g. for ABC pillars)
  • Seat upholstery constructions
  • Sound and heat insulation parts and trim parts in the engine, passenger and trunk
  • Filter materials for air, oil, fuel and cabin filter elements
  • Carrier material for adhesive tapes for wrapping cable harnesses

Plastics industry

Electrical engineering

  • impregnated flexible multilayer insulating materials (e.g. nonwoven-film-nonwoven)
  • Prepregs , d. H. Nonwovens pre-impregnated with electrical insulation resins for insulation in electrical machines and transformers
  • Processing aid for mica tapes
  • Cable nonwovens in semiconducting and non-conductive design in combination with superabsorbents as water blockers for damaged underground cables ("swelling nonwovens")
  • Conductive nonwovens as shielding in cables
  • Thermal, separating, fixing and rodent protection layers in cables
  • Battery separators
  • Nonwovens made of carbon fibers in gas diffusion layers of fuel cells for the supply and removal of the reactants, products and the free electrons

Agriculture and horticulture

  • Premature and protective nonwovens for temperature management
  • Nonwovens for chemical-free weed control
  • light-absorbing or reflective nonwovens for light management
  • Nonwovens as insect repellants
  • Irrigation nonwovens on greenhouse tables
  • Plant growing pots


Historical development of nonwovens production

From the origins to 1850

For several thousand years, the nonwoven fabric has been the preliminary product for sufficiently strong and therefore usable textile fabrics, which we have been summarizing under the term nonwovens since the middle of the 20th century.

Wool or hair felts , which were originally produced with the help of such "chemical aids" as hot water, urine and whey, by stamping with the feet and by tapping layers of fibers made from animal hair (fleeces), are certainly among the oldest of Man-made textile fabrics and the origins of nonwovens. Finds from different parts of the world (Central Asia, Scandinavia, Northern Germany and Siberia) of products made of felt are dated from 1500–1000 BC. Dated.

The hand-made long fiber papers , as they were processed into clothing (e.g. kimonos ) in China in times before the year 1000 , as well as the lesser-known tapas made from tree bark components in Polynesia and Melanesia , which were used to make clothing, can also be used. are regarded as preliminary stages of nonwovens. As an early form of a nonwoven fabric made of filaments (spunbonded nonwoven) an occupied by the Chinese likewise already around 1000 method can be considered, in which the of the bead of the silkworm drain produced yarn on a flat surface and not a cocoon spun let . The fabric produced was z. B. processed into hand fans .

Glued wadding was already known in France at least at the beginning of the 19th century and was produced as panels or sheets and used as underlayers or intermediate layers for items of clothing and can therefore be regarded as the forerunners of interlining nonwovens. Webs of cotton , silk fiber waste or only tow , which initially still with hand using a specialized arc, later using so-called Kardätschmaschinen ( carding ) used for fiber preparation in the yarn used for some time and bewerkstelligten a meshing processing of pre-cleaned fiber batts, are with Gluing from z. B. rabbit skins have been solidified.

From 1850 to 1945

The padding made from shredded wool , d. H. Recycled used textiles or waste from textile manufacturing processes, produced and partially solidified on the surface by gluing, came onto the market in the second half of the 19th century and can be seen as the forerunners of today's upholstery nonwovens.

Also from the period from the middle to the end of the 19th century, the consolidation of nonwovens by needling using z. B. Barb needles reported. A large number of needles arranged next to one another on a so-called needle board or bar pierce the fleece back and forth. As a result, the fibers are intertwined and the fleece is thus consolidated into a fleece or, as is still often referred to, into a needle felt. The advantage of this new consolidation process was that no feltable fibers, such as those required in the manufacture of fulled felts, were required. US Pat . No. 123,136 from 1872 describes a machine with which it became possible to consolidate nonwovens using needles. The first jute and sisal needle punched fabrics were produced in Great Britain and the United States in the 1890s . They were mainly used as underlay for carpets . Since then, manufacturers of needling machines for strengthening nonwovens have been Bywater, Great Britain, and Hunter, USA.

Starting around 1900, and increasing from the mid-1930s, there was an increasing number of patents in Germany as well as in the USA and Great Britain, which dealt with the consolidation of nonwovens using adhesives ( binders ). The nonwovens were produced on the fiber preparation machines used for yarn production, with the fiber webs (nonwovens) being placed directly at the end of the card or card on a conveyor belt moving in the machine direction. So-called parallel fleeces were created with predominantly longitudinally oriented fibers, which ultimately led to anisotropy , especially of the mechanical properties. For the introduction of the binding agent into the fleece, machines and chemical agents known from textile finishing were often used , which were known from the finishing of traditional textile fabrics. The goal was mostly to create a leather substitute . It is not always known to what extent the patents were realized commercially. In any case, the German patent No. 544 324 from 1928, registered by Adolf Schoeler, was used, according to which nonwovens from the company WEIKA, a predecessor of today's KALFF Vliesstoffe GmbH, were consolidated by adhesives (e.g. gutta-percha ) as early as 1928. under the brand name Capama -stoffe ® , which were used as an intermediate lining , reinforcement, cushioning and covering insole for the manufacture of shoes .

The development work carried out by Carl Ludwig Nottebohm at Carl Freudenberg , Weinheim for the manufacture of nonwovens from the mid-1930s onwards became significant for the beginnings of nonwovens production in Germany . In April 1936, Nottebohm offered the company its development work as an opportunity to produce artificial leather . From 1937, an artificial leather based was Freudenberg a nonwoven fabric from native raw materials using cottonisiertem hemp (h. Hemp short fibers d.) And rayon (viscose) and a polyvinyl acetate dispersion as a binder, which the then self-sufficiency efforts came to meet. After the Second World War , interest in artificial leather declined again in Germany, as leather imports became possible again. For this reason, the systems available at Freudenberg were used to manufacture interlining nonwovens and wipes on a nonwoven basis, which came onto the market from 1948 under the brand names Vlieseline ® and Vileda ® .

In contrast to Germany, where the formation of nonwovens for the manufacture of nonwovens was mainly based on the usual textile fiber preparation techniques, in the USA the production technology of papers for the manufacture of nonwovens was assumed. As early as 1933 in the USA, the Dexter company was the first to process long textile fibers from the fiber banana (abaca fibers ) on paper machines into nonwovens, which were used to manufacture tea bags . During the Second World War, modified paper-making processes were used primarily to process the excess of inferior cotton (short fibers) into nonwovens at low cost. From this, hygiene articles such as handkerchiefs , napkins , cosmetic tissues for single use were made.

Since the 1950s

From 1945, but especially from the beginning of the 1950s, more and more companies and research institutes began to produce nonwovens in order to save manufacturing costs for textiles and to be able to process waste or previously unusable materials into fabrics. In addition, it was discovered that conventionally manufactured textiles were oversized for certain applications. However, the euphoric expectations of being able to replace all previously known textiles with nonwovens soon gave way to more realistic ones, which was also due to the aesthetics of the nonwovens . At an early stage, therefore, the focus was on the use of nonwovens in technical applications, where aesthetics were not so in the foreground, but the use of fiber properties and the structure, which can be regulated within wide limits.

Since the cards and cards available in the mid-1940s only produced fiber webs, the fibers of which were very strongly oriented in the longitudinal direction and thus caused anisotropy of the strength values, which was unfavorable for an increasing number of applications, developments of high-performance compensating stackers (cross panels) were made. (e.g. described in US Pat. No. 2,565,647 “ Cross-Laying Machine ” dated June 24, 1946), although similar devices were already known in earlier patents in simple designs from felt production (so-called cross-fur machines). The cross-stacker removes the fiber web from the card and places it by moving back and forth on a storage and transport belt running transversely to its direction of movement. By controlling the speed of this depositing belt which may basis weight of the resulting multi-layer web, and the deposition angle of the fibers are controlled in this web. Cross-ply fleeces are created. Likewise, the width of the storage table can also be used to redefine the width of the fleece compared to the pile width removed from the card. In the course of time, improvements were made to the web layers with regard to the laying speed, as this had to be adapted to the desired higher nonwoven production speeds in the overall system. Only to increase the surface weight of the fleece while maintaining the longitudinal orientation of the card pile, the surface weight of which can be between 6-70 g / m², several cards were and are arranged one behind the other to form the pile in layers on a belt to form a fleece, which is fed to the consolidation unit to discard. So-called parallel fleeces are created. The weight per unit area of ​​the differently manufactured nonwovens can be between 20 and 2500 g / m² depending on the type of deposit and fiber type and the desired properties of the nonwoven.

In the mid-1940s, development work began on a process for forming nonwovens from random webs, i.e. H. Nonwovens in which the fibers were distributed in all directions in the plane, which led to an isotropy of the properties, which was favorable for a large number of applications. It was also important that single-layer nonwovens could be achieved in a wide range of basis weights and thus delamination , as can occur with nonwovens made of layered nonwovens in certain consolidation processes and applications, is prevented. Air currents were used to separate the fibers instead of water, as was used in the wet web technology derived from paper production. The formation of fleece by means of an aerodynamic process was first offered commercially by the Curlator Corp./USA as a system under the name Rando Webber in 1947/1948. From that time on, systems of this type, developed by numerous companies, spread very quickly and became widely used in the manufacture of nonwovens. It is interesting that very short, non-spinnable fibers could also be used for fleece formation in the dry way. Flock pulp could be processed together with longer fibers, which became of enormous importance especially for the production of absorbent nonwovens for hygiene, medical and cleaning products.

From the 1950s onwards, the interests of the chemical industry in this newly developing sales market had a major influence on the further development of nonwovens, in particular the expansion of the chemical fiber production and the production of plastic dispersions as binders for the nonwovens industry. These branches of plastics technology and plastics production thus became, alongside the textile and paper industry, an important, if not the most important, mainstay of nonwovens production. The production of special binding fibers, which could be used as so-called adhesive fibers as binders in thermal bonding processes, became important for the manufacture of nonwovens. The bicomponent fibers invented as early as the 1930s came back later. H. Fibers with two different components, mostly as core-sheath fibers with a sheath that melts at lower temperatures compared to the main component, the core, in the case of nonwovens that are solidified by the action of heat. In addition, there were inventions of island-in-the-sea fibers, in which the finest fiber fibrils are enclosed in a matrix, which are dissolved after the formation of the fleece and a corresponding fleece made of fine fibers, which came close to the collagen fibers of the leather in their fineness, left behind. B. was suitable for bonding with polyurethane . As a result, from 1973 onwards, nonwovens were obtained that could serve as a leather substitute (e.g. Alcantara ® ). In later years, the production of bicomponent films , which could be converted into nonwovens by fibrillation or splitting and then predominantly bonded to nonwovens using mechanical bonding processes, became important for the manufacture of nonwovens.

The development work carried out in the 1950s, in particular by DuPont / USA and Freudenberg / Germany, for the production of nonwovens, in which filaments (continuous fibers, elementary filaments ) are extruded and drawn directly from a polymer melt through nozzles arranged next to one another in a spinning beam, became even more relevant and with the usual fiber diameters of 10 to 35 µm are placed on a storage and transport belt. These continuous fiber layers are additionally consolidated by means of calender rollers and result in so-called spunbonded nonwovens (spunlaid nonwovens), a variant of the nonwovens produced by extrusion processes. Typically, nonwovens are produced with a basis weight between 10 and 200 g / m², whereby to increase the basis weight, but also to improve the uniformity of several spinning beams arranged one behind the other, nonwovens are laid on top of one another and then consolidated. Such a manufacturing process had been known since the application for US Pat. No. 2,336,745 in 1941. 1965 DuPont and Freudenberg started producing polyester- based spunbonded nonwovens (Reemay® and Viledon®).

Over the years, numerous process variants for the production of melt- spun nonwovens have been added, especially with regard to the polymers used (including polypropylene , polyamide , polyethylene ), but spunbond nonwovens with filaments on a core-sheath basis have also gained importance. The systems used to manufacture such nonwovens had a high level of automation right from the start and, over the years, were continuously improved in terms of their system speed and width in order to be able to cover the growing demand for nonwovens, especially in the hygiene and medical sectors.

From the mid-1950s, DuPont / USA developed a special process, the flash spinning process ( relaxation evaporation spunbond process ), in which a superheated solution of high-density polyethylene (PE-HD ) under high pressure in an autoclave ), which is passed through nozzles and an explosion-like relaxation occurs at the nozzle outlet. The filaments emerging from the nozzle are fibrillated and deposited as three-dimensional fine fiber networks (fiber diameter between 0.5 and 10 µm) on a storage and transport belt. These fiber layers are then consolidated by means of calenders under pressure and heat. This type of fine fiber fleece has been produced exclusively by DuPont in various product variants under the brand name Tyvek ® since 1967 .

Another group of processes for forming nonwovens directly from polymer melts was introduced to the market in the early 1970s, after the Naval Research Laboratory, Washington, published a first publication in 1956. These fibers (a mixture of continuous fibers and mostly shorter fiber filament sections, which are created by the high load when stretching the fibers in the hot air), were produced by the meltblowing process and deposited on a storage surface that was used as a conveyor belt at the same time, had fiber diameters of usually two to seven Micrometer (µm), so that a very high density of the deposited fleece could be achieved and thus became particularly interesting for filtration or as a barrier material because of the high degree of separation of the finest particles. The concept of this process went back to the production of mineral wool and slag wool , which was already known before 1840 . The US group Exxon developed the meltblown process on the basis of various meltable polymers in the late 1960s / early 1970s to market maturity, so that such systems could already be produced in the early 1970s and glass fiber nonwovens in the filters of protective masks through this new product group unbreakable fibers could be replaced. A further development of the process by the plant manufacturer Hills Inc./USA should even be able to join fibers with a diameter of less than 400 nanometers (nm), which in this field of application are usually referred to as nanofibers , to form a fleece. The strength of these fiber structures, which are produced using the meltblown process, are too low when the products have a low mass per unit area, which is why they need to be covered on both sides and thus led to the development and production of combined nonwovens made of spunbonded nonwovens (S) and meltblown nonwovens (M), which are produced on one plant by connecting the various fiber production units in series. These nonwovens are known under such names as SMS or SMMS nonwovens.

In 1980, Freudenberg / Germany announced that they could use an electrostatic spinning process to produce very fine polymer fibers with a diameter of preferably between one and ten micrometers (µm) and lay them down to form uniform nonwovens in one production step. The fiber lengths reached a few millimeters to a few centimeters. Because of the low mechanical strength of the fibers, this fleece required that both sides be covered with other fleece. The application of the composite nonwoven that ultimately resulted was in ultra-fine filtration for air (e.g. pocket filters or breathing masks). The process described by Freudenberg was evidently based on development work by Bayer AG / Germany, which is laid down in the Offenlegungsschrift 2328013 “ Process for the production of fiber filters by electrostatic spinning ” of June 1, 1973. With this electrostatic spinning process, which was already described by the German Anton Formhals in several patents in the 1930s (e.g. as the first in DRP -Nr. 661 204 of December 1, 1934) and to which from the 1970s / A large number of other patents were added at the beginning of the 1980s, in addition to polymers from melts, especially those from polymer solutions are converted into ultra-fine fiber fleeces , such as polycarbonate fibers , which have an electret effect and thus contribute even more effectively to the separation of dust particles in ultra-fine filters. The aim of the more recent development work from the late 1990s / early 2000s by numerous institutes was and is to securely manufacture fibers with a diameter in the lower nanometer range and to deposit them into fiber layers, because even more effective filter and barrier nonwovens can be produced with such fiber diameters. However, at the beginning of the 2000s, the Donaldson Company from the USA announced that it had been producing filter material complexes using nonwoven layers of polymeric nanofibers with a diameter of 250 nm for more than 20 years and used them for a wide variety of filter elements.

A process that is certainly not too important in terms of the scope of production, but is interesting because of its uniqueness, produces continuous fiber nonwovens based on cellulose. This process makes use of the solubility of cellulose (mostly cotton linters) in an aqueous ammonia solution containing copper oxide and is based on the draw spinning process for the production of so-called copper silk (copper oxide ammonia silk) by the German company JP Bemberg . This "Bemberg fiber technology" was specially developed by Asahi Chemical Industry (ACI) / Japan from the 1960s. From 1974 onwards, the development work led to the production of the cellulose spunbonded nonwoven Bemliese TM , which is highly absorbent, meets high hygiene standards (contains no binding agents) and, in particular, is lint-free because of the continuous fibers. B. is necessary for cleaning wipes in the clean room.

New processes were also added for the strengthening of nonwovens based on textile staple fibers. After already in the 1950s, in particular in the former RGW -Staaten Czechoslovakia and DDR for example, have been developed new methods for mechanical web consolidation, in which preferably webs with transverse to the machine direction fibers (transverse fiber webs) by means of mesh-forming yarns (z Vliesnähwirk method. Maliwatt - first Machine in operation in the GDR in 1954 - or the Arachne process in the ČSR) or by direct loop formation from the transverse fiber fleece presented using compound needles (e.g. Malifleece fiber fleece knitting process), one began at the end of the 1950s to the beginning of the 1960s with the development of processes in which the fibers of a pre-laid fleece were swirled and entwined by means of focused water jets and the fleece was thus consolidated.

The American company Chicopee / USA (integrated in the Polymer Group Inc./USA) started this by using a special technique to use low-pressure water jets from inside a perforated drum against the non-woven fabric, which was placed on an open-structured screen belt, for patterning and light solidification. The patterned fleece was also strengthened by binding agents. This so-called keybak technology is still used in particular for the production of nonwovens for cleaning wipes. From 1969 these products were produced commercially. In the 1960s, DuPont was working on development work on the production of nonwovens using water jets to swirl and thus strengthen the fiber webs presented. High-speed streams of water jets were used so that sufficient overall consolidation could be achieved and thus binder-free nonwovens could be produced. These "spunlaced" or "hydroentangled" products were launched on the market under the brand name Sontara ® . Polyester fibers, viscose fibers or mixtures with cellulose were consolidated to form nonwovens with both a closed and a patterned (apertured) structure. After the release of DuPont's key patents in 1976, a rapid development of systems for the production of nonwovens bonded by means of water-jet began. The first production line in Europe was put into operation in 1983 in Wiesenbad / Saxony in a predecessor company of today's Norafin Industries / Germany. It was based on joint development work with the Research Institute for Textile Technology, a predecessor of today's Saxon Textile Research Institute (STFI), Chemnitz / Germany. Nonwovens for compresses and base materials for synthetic leather production were manufactured.

From the 1990s, more and more commercial production plants were built, with the plant widths and production speeds, but also the pressures of the water jets being increased. As a result, from the end of the 1990s, nonwovens consolidated with water jets with up to 400 g / m² and more as well as with fabric inserts (APEX ® technology, PGI / USA) could be commercially produced, which compete with needle punched nonwovens in the filter media sector could and even achieved an advantage due to the uniform surface. A further step was the first spunbond spunlace line, which Freudenberg Germany put into operation in 2000. Splittable bicomponent filaments (e.g. built up as a cake structure from PA / PET sections) are extruded on a spunbond device, laid down as a fleece and bombarded with water jets, which results in the fibers splitting into fine filaments of approx. 0.15 dtex that are swirled and thus solidified. This creates nonwovens with a very textile character with a wide range of applications. They are on the market under the brand name Evolon ® .

All of the web formation and web bonding processes described here in their historical development are in use, only their proportions in the overall scope of nonwovens production have shifted; in the 1950s and 1960s, the proportion of nonwovens bonded with binders was significantly higher. Constant improvements in the efficiency of the processes and the quality of the nonwovens through the use of the latest monitoring and control technology are characteristic of the production of nonwovens since their market launch. Starting with a few thousand tons in the early 1940s, around eight million tons of nonwovens were produced worldwide in 2012.


  • Hilmar Fuchs , Wilhelm Albrecht (Ed.): Nonwovens. Raw materials, manufacture, application, properties, testing. 2nd edition, WILEY-VCH Verlag, Weinheim 2012, ISBN 978-3-527-31519-2 .

Web links

Individual evidence

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