Flax fiber

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Flax fiber
Flax fibers
Fiber type

Natural fiber

origin

Common flax

properties
Fiber length Single fiber 9-70, average 33 mm; Fiber bundle 250-1200 mm
Fiber diameter 5–38 µm, avg. 19 µm
density 1.4 g / cm³
tensile strenght 0.90 GPa
Specific tensile strength 0.60 GPa
modulus of elasticity 85 GPa
Specific modulus of elasticity 71 GPa
Elongation at break 1.8 ... 3.3%
Water absorption 7%
Products textiles
Flax fibers

As linen (such as medium high German līnīin , "party, from flax, Linum usitatissimum" to ancient Greek linon and Latin linum , flax ') or flax , both the fiber of the commons linseed and in particular in the linen industry made therefrom tissue referred to, the latter also called canvas , sheet or linen . As with cotton , hemp , wool and silk , it is a natural fiber . Linen can be spun well , is boil-proof , very tear-resistant and does not form fluff , but it is comparatively difficult to iron.

Since the late 19th century, linen has been almost completely replaced by cotton in the textile industry , but has been gaining importance again as an ecological natural fiber since the end of the 20th century.

The fiber

The flax or linen fiber is obtained from the stalks of the flax plant and is one of the bast fibers . The linen fibers form bundles, in contrast to seed fibers like cotton, which consist of unconnected individual fibers. The 2.5 to 6 centimeter long cellulose elementary fibers are connected by pectins to form 50 to 90 centimeter long fiber bundles, the technical fibers. Other components of the fiber are hemicellulose and lignin . The amount of the individual components depends on the degree of ripeness of the fiber, on average a flax fiber consists of 71% cellulose, 18.6 to 20.6% hemicellulose, 2.3% pectin and 2.2% lignin and around 1.7% wax which can be found for the most part on the fiber surface. By means of cotonization (also known as cotonization , cotonization or cottonization ), the bundles can be broken down into elementary fibers using various methods. Since cottonizing was primarily based on the use of thin alkalis to dissolve the pectins, it was no longer practiced in Europe for a long time for reasons of environmental protection. It has only been topical again since the end of the 20th century, such as the steam digestion process , improved mechanical processes and ultrasonic processes.

The thus produced Flockenbast ( flakes flax ) fits with its fiber length distribution of up to 40 millimeters in the length range of the cotton fiber and therefore, in the short-staple spinning mill (three-cylinder spinning, cotton spinning) are spun in pure form or in mixture with other short fibers into yarns.

harvest

Sheaves of pulled flax placed in the field

At harvest, the flax plants are using special machinery to the roots from the soil scuffled , that is pulled because the fibers are destroyed when mowing. The harvest takes place when it is yellow, then the leaves in the lower third have already fallen off. The straw is placed in a swath on the ground and aligned parallel. During the subsequent drying process, the epidermis tears open so that later microorganisms can penetrate here. The fluting removes the flax seed pods . The corrugation can also be done after roasting . During roasting or rotting, the bond between the fiber bundles and the surrounding tissue is broken by bacteria and fungi . The rotting must be interrupted at the right time to prevent damage to the fibers.

Dew roast in the field

The prevailing today roasting method is the Tauröste applied to around three quarters of the world's arable land, especially in areas with oceanic climate, since this dew moisture is needed. The flax straw is left on the fields. The dew moisture causes bacteria and fungi to break down the pectins. This process is relatively environmentally friendly, and some of the nutrients are returned to the soil during roasting. Disadvantages are the susceptibility to the weather and the long duration.

In some areas, e.g. B. in Eastern Europe, Belgium, China and Egypt, the hot water roasting is used. Here the straw is roasted for three to four days in pools with water at 28 to 40 ° C. This leads to quite high environmental pollution through the sewage.

A historical process is cold water roasting , in which the flax straw was roasted in ponds or in moats (so-called flax roasting ). Chemical roasting processes have not caught on because they usually attack the flax fibers. Enzymatic processes have not caught on for reasons of cost.

Extraction of the fibers

Processing of the flax fiber schematically
breaking, swinging, panting
"Flax" showcase from raw material to end product
Flax fibers

After roasting, the straw is dried again and brought to the processing plants (Schwingerei, Haarhaus, Brechhaus). Here the straw is first broken : the wood core is cut into small pieces, scrapings called crushed. During the subsequent swing, the shives are separated from the flax, which also results in the swing , short flax fibers. Shives and flyworms are separated from each other in a tow cleaning system. The flax is hackled and parallelized and further cleaned. The flax fibers, also known as long fibers, leave the Schwingerei twisted into braids and are brought into the spinning mills.

Short fibers are either a by-product of long fiber production or the entire production is geared towards short fibers. Then the processing takes place in a so-called short fiber line: The straw is not processed lying parallel. The resulting short fibers are not as highly purified as the long fibers and are mainly used for technical purposes.

Textile processing

be crazy

When spinning , the fibers are spun into threads. Long and short fibers are handled differently, a distinction is made between dry and wet spinning processes.

Before spinning, long fibers are combined into a ribbon, stretched several times and mixed (doubled) with other ribbons in order to achieve the most homogeneous possible quality. Long fibers are usually spun wet into high-quality threads. The ribbons are stretched into fine, homogeneous threads. The pectins dissolve in a warm water bath at 70 ° C , so that the fibers warp against each other more easily. After being wound on spools of thread, the thread is dried at around 80 ° C.

In the case of short fibers, a flat "fleece" is produced by roughening (carding), which is reduced to a band. This tape is combed (tickled) to clean it of shives and fibers that are too short. Then the tape is stretched and doubled like the long fibers. Short fibers are usually dry spun. The resulting yarns are rough and at the same time feel soft.

Weave

Linen is woven in the classic plain weave , but jacquard , twill and other types of weave are also common. Batiste , veil and linon were also made from flax, but they were not counted as linen. When weaving linen, a very even and therefore expensive yarn must be used for the warp threads . Warp threads with the irregularities typical of linen would suffer from the abrasion and tear too often.

Half- linen is a fabric with a minimum content of linen fibers; it is typically woven with linen as the weft and mostly cotton warp threads.

properties

Textile fiber

Compared to other bast fibers, the linen fiber is easily divisible and finely spun, which makes it stand out for laundry and clothing. The linen fiber is smooth and the linen fabric traps little air, so linen is lint-free and less susceptible to dirt and bacteria, the fiber is naturally bactericidal, almost antistatic and dirt-repellent.

Linen absorbs up to 35% humidity and exchanges this humidity quickly with the ambient air, thus having a cooling effect, but is still warm and dry. That is why the fabric is often used for summer clothing. The water retention on the surface is also the cause of the antistatic (and therefore dirt-repellent) property. The linen fiber is very tear-resistant and extremely inelastic. Due to its low elasticity, linen is prone to creasing; the tear resistance makes the linen hard-wearing and durable. Linen is strong and does not need to be strengthened like cotton. It has natural shine and strength.

However, linen is susceptible to friction. Its abrasion resistance is lower than that of cotton; The gentle cycle should therefore be used for washing or only compressed and not rubbed for hand washing.

Linen is insensitive to detergents, detergents, hot laundry, dry cleaning and high temperatures when ironing. Dry heat damages the fabric, so it must still be slightly damp for ironing; tumble dryers are not suitable.

The bleaching of linen is problematic. Full bleach results in weight loss of up to a fifth. The dyeing of linen is possible in the yarn or on the fabric. The blue of the workwear is due to the dyeing behavior of the linen, which could only be dyed reasonably realistically with natural colors with indigo . This is due to the property of linen as a cellulose fiber, which does not allow chemical bonding during dyeing. In addition to the vat dyes mentioned, coloring is also possible with the class of substantive dyes . The dye molecule - only mechanically captured - is incorporated into the tangle of the polymeric cellulose molecule.

Technical fiber

The technical flax fibers are relatively stiff and tear-resistant. Combined with their low density , they have a high specific strength and rigidity, comparable to glass fibers. Flax fibers are therefore also used for technical fabrics and as a substitute for asbestos fibers.

However, the quality of the fibers depends heavily on the cultivation conditions and digestion method, which results in a relatively large scatter. However , these fluctuations can be controlled through consistent quality management .

use

Flax: straw, yarn and ropes

linen

Linen fabrics have traditionally been used for bed and house linen. In this use they were replaced by the cheaper cotton. New areas of application such as clothing and decorative fabrics are added, especially in the form of hand-woven high-priced products. Linen is used as an upholstery fabric for book covers, as well as for shoes, bags and high-quality acupressure mats . Linen fabrics for covering canvases in painting gave it its name. Linen straw is becoming increasingly important as litter in horse keeping. The woody part of the flax stem is used for this. The suction power is ten times as high as that of ordinary straw, four times as high as that of wood chips.

Stiff linen is a hard-finished, inelastic lining made of linen, linen tow or half linen . Softly finished it is called quilting linen, not finished blocky linen .

Ropes

Ropes made of flax fibers were used, among other things, in nautical ropes . The word "line" refers to the fact, as derived words such as washing line , fishing line , lanyard or leash , even if these items are today mostly not made more out of flax.

Insulation material

Short fibers, which are a by-product of linen production, are used to produce natural insulation materials in the form of mats, panels or darning wool, and occasionally a little polyester is added to make them more stable . Flax has a WLG value of 040 and is therefore comparable to wood fiber, cellulose , rock wool or polystyrene and stores heat well with a heat capacity of 1550 J / (kg · K). It is classified in building material class B2, so it is normally flammable. Although the corresponding products have established themselves as thermal insulation materials, the market share of linen in the insulation material sector is currently - together with hemp - less than 0.5%, even under optimal conditions, a market share of at most 5% is also expected for the future .

Natural fiber composites

Due to its good mechanical properties and regional availability, flax fibers are increasingly used as reinforcing fibers for natural fiber composites. In addition, the price of technical fibers, well below one euro per kilogram, has fluctuated only slightly in recent years.

One of the most important areas of application for flax fiber-reinforced plastics is the automotive industry ; almost two thirds of the natural fibers used here are flax fibers. In recent years, however, other industries have also been among the customers.

The fibers used for the production of natural fiber reinforced plastics are mainly short fibers due to their price. One of the most important processing methods for natural fibers is compression molding , in which so-called fiber mats are pressed together with thermosetting or thermoplastic plastics under the influence of temperature. Flax fibers can also be found in plastic granulates for injection molding and extrusion processing . These materials are characterized by a low density combined with relatively high strength and rigidity. In combination with the sustainability of natural fibers, their CO 2 -neutrality and medical safety, there are great savings opportunities for fiber-reinforced and filled plastics.

Name and quality

The CELC awards the masters of linen seal, a protected trademark, to linen products from Western European cultivation. The four characters with the stylized "L" stand for qualities from pure linen to half linen.

In Germany, until the beginning of 2016, according to Annex 1 No. 7 of the Textile Labeling Act, the terms flax or linen for bast fibers from the stalks of flax (Linum usitatissimum) and half linen ( Section 5 (5) TextilKennzG old version) for products with a chain made of pure cotton and a Weft made of pure linen, in which the proportion of linen makes up no less than 40% of the total weight of the desized fabric, whereby the indication “warp pure cotton - weft pure linen” must be added. Pure linen must contain pure flax yarn in the warp and weft. The abbreviation for the fiber raw material flax / linen is LI (proportions of raw materials in blended fabrics); only linen without other fibers may be called “linen, pure” (both warp and weft made of linen only).

Since the revision of the Textile Labeling Act in February 2016, reference has been made to the provisions of Regulation (EU) No. 1007/2011.

Economy and ecology

Map showing the linen industry in Germany around 1930

The share of linen in the global fiber volume is only around two percent. The largest cultivation areas are China with 161,000, the EU with 102,740 (mainly France and Belgium), Russia with 89,210, Belarus with 71,000, Ukraine with 23,600 and Egypt with 8,900 hectares. In Germany with 30 and Austria with 129 hectares the cultivation is meaningless. World production is around two million tons annually.

Most of the added value in flax fiber cultivation is made with long fibers, which make up around 88% of sales in the EU. In 2003 the price for a ton of long textile fibers was 1,593 euros, for short textile fibers at 345 euros, for short fibers for paper at 170 euros, and for short fibers for insulation or composite materials at 400 to 500 euros. The majority of European long fiber production is exported, especially to China.

In contrast to cotton, linen production is dependent on the use of little chemicals ( fertilizers , pesticides ). Linen can also be produced without modern technology, but the production of linen fibers is complex and labor-intensive. Cotton only caught on with industrialization , with this trend towards mass production in turn influencing the amount grown.
On the other hand, linen is the only natural fiber that is on the market in controlled organic quality from local cultivation (Western Europe). An ecological production of flax fibers on a large scale is limited by the problems of harvest and taurotte . Wastewater from the Wasserrotte is polluted, so the Taurotte is recommended and encouraged.

history

Preserved remains of an ancient linen fabric from the Dead Sea

488 flax fibers - including 58 allegedly dyed fibers - are considered the oldest evidence of the manufacture of clothing. They come from the Dzudzuana Cave in Georgia and were recovered in 2007 and 2008 from a layer of soil whose age was dated to 36,000 to 31,000 years (yr BP ka). The oldest flax processing in Central Europe can be found in the Moravian mammoth hunter station Dolni Vestonice and is approx. 28,000 years old. Egyptian mummies are wrapped in strips of linen. In ancient Greece, linen was used to make linen armor, in Greek linothorax . They were considered so precious that they were offered as consecration gifts in the temples.

From Greek and Roman antiquity to the European Middle Ages , linen was the material for clothing alongside wool . Linen had its heyday in pre-industrial Europe. When cotton was not yet imported in large quantities, linen was the only vegetable fiber (with a few exceptions). By the end of the 18th century, 18% of the fibers processed were from flax and 78% from wool.

In the Middle Ages, linen (in contrast to wool) was preferred for use close to the body due to its dirt-repellent properties, and due to its strength also for cloth armor. Since it was difficult to dye, it was mainly offered in pale tones; opaque and dark tones were expensive. For a long time linen was only processed by hand , later industrial methods were added. Until the 20th century, hand-spun, but also machine-spun yarn was woven by hand on hand looms, e. B. in the winter months on farms ( farm linen ). Flax processing equipment can therefore be found today in countless local and open-air museums . The linen was mainly processed in Ireland, Holland , Westphalia , Saxony , Silesia , Bohemia and the St. Gallen region in Eastern Switzerland .

The National Socialist regime pushed the cultivation of flax as part of its political self-sufficiency efforts . The area under cultivation increased from 5,000 hectares in 1933 to 100,000 hectares in 1937. Flax plants were built to process the fiber, for example in Künzelsau in 1937 .

The following qualities are historically distinguished:

  • Flax canvas - pure long fiber flax in a plain weave
  • semi-flat or semi-knotted linen - woven with yarn from long fiber flax and tow
  • Half sheets - woven with flax yarn as warp and tow yarn as weft
  • Semi-cotton or half -linen - woven with cotton and linen yarn
  • House canvas - woven by hand
  • Irish or Irish - woven with cotton as warp and flax yarn as weft
  • White thread canvas and lion linen - woven with bleached thread
  • Wergle canvas or Hedelinen - woven with yarn from Hechelwerg, or vice versa.

Fabrics made from hemp in plain weave were also referred to as linen ( hemp canvas ).

With the perfection of machine cotton processing at the beginning of the 19th century, linen was pushed back first in America and later with growing cotton imports in Europe. After another low point at the beginning of the 1980s, consumption is slowly increasing, with the trend towards natural fabrics, hand-woven articles and high-priced handicraft fabrics as well as cultural and historical reproductions promoting growth.

After entire rows of houses burned down in many villages, strict regulations were issued in the 18th century under Count Palatine Karl IV to prevent a fire, which also regulated the proper handling of flax.

Museums and monuments

Flax crushing hut and kiln in Creglingen-Burgstall
Flax processing in the open-air museum Roscheider Hof

literature

  • Frank Waskow: Hemp & Co. The renaissance of domestic fiber plants. Edited by the Catalysis Institute. Verlag 'Die Werkstatt', Göttingen 1995, ISBN 3-89533-138-4 , pp. 93-144.
  • Alfons Hofer: Fabrics. Volume 1: Raw materials: fibers, yarns and effects. 8th edition. Deutscher Fachverlag, Frankfurt am Main 2000, ISBN 3-87150-671-0 .
  • Ursula Völker, Katrin Brückner: From fiber to fabric: textile material and goods science. 32nd edition. Publishing house Dr. Felix Büchner / Verlag Handwerk und Technik, Hamburg 2001, ISBN 3-582-05112-9 .
  • Hannelore Eberle: Expertise in clothing. 8th edition. Verlag Europa-Lehrmittel, Leipzig 2005, ISBN 3-8085-6208-0 .
  • HL Bos: The Potential of Flax Fibers as Reinforcement for Composite Materials. Dissertation. Department of Chemical Engineering, Technical University Eindhoven, The Netherlands 2004.
  • Michael Carus et al: Study on the market and competitive situation for natural fibers and natural fiber materials (Germany and EU). Agency for Renewable Resources (FNR), 2008.
  • Patricia Baines: Linen: Hand Spinning and Weaving. Batsford, London 1989, ISBN 0-7134-4779-6 .
  • Bert Dewilde: Flax in Flanders throughout the centuries: History, Technical Evolution, Folklore. Lannoo, Tielt 1999.
  • Marianne Fasse: From flax and linen in ancient times. Reports and pictures, documents and records. Güth, Rheda-Wiedenbruck 1989, ISBN 3-922828-40-X .
  • Max Flad: Flax and linen: From flax cultivation, spinning and weaving in Upper Swabia and on the Alb . Schwäbischer Bauer publishing house, Ravensburg 1984, DNB 850598753 .
  • Klaus Freckmann, Gabriel Simons, Konrad Grunsky-Peper: Flax in the Rhineland: Cultivation and processing. (Series of publications by the Sobernheim Open Air Museum; 6). Rheinland-Verlag, Cologne 1979, ISBN 3-7927-0516-8 .
  • Horst Hagen, Hermann Tödter: Flax becomes linen: growing and processing flax, an old rural craft. (Rotenburger Schriften special volume; 29). Rotenburg / Wümme 1985, OCLC 256066526 .
  • Gabriele Harzheim: The blue miracle: Rhenish flax and linen production in the 19th century. (Writings of the Rheinisches Freilichtmuseums - Landesmuseum für Volkskunde; 35). Rheinland-Verlag, Cologne 1989, ISBN 3-7927-1092-7 .
  • Gabriele Harzheim: linen weaving and bleaching. (Regional and folkloric film documentation; 5). Rheinland-Verlag, Cologne 1990, ISBN 3-7927-1184-2 .
  • Udelgard Körber-Grohne: Useful Plants in Germany: Cultural History and Biology. 3rd, unchanged. Edition. Theiss, Stuttgart 1994, ISBN 3-8062-1116-7 .
  • Eduard Schoneweg: The linen trade in the county of Ravensberg: A contribution to Low German folklore and antiquity. Reprint after d. 2nd Edition. v. 1923. Wenner, Osnabrück 1985, ISBN 3-87898-293-3 .

Web links

Commons : Linen (flax)  - Collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d e f g h i Comparative physical, chemical and morphological characteristics of certain fibers. In: Robert R. Franck: Bast and other plant fiber s. Woodhead Publishing, Cambridge 2005, pp. 4-23.
  2. ^ AK Mohanty, M. Misra, G. Hinrichsen: Biofibres, biodegradable polymers and biocomposites: An overview . Macromolecular Materials and Engineering, 2000, Issue 276, pp. 1-24.
  3. ^ Alois Kießling, Max Matthes: Textile - specialist dictionary . Fachverlag Schiele & Schön, Berlin 1993, ISBN 3-7949-0546-6 , p. 216.
  4. ^ Paul-August Koch, Günther Satlow: Large Textile Lexicon. Specialized lexicon for the entire textile industry. Deutsche Verlags-Anstalt, Stuttgart 1965, Vol. A – K, p. 248.
  5. ↑ Fabia Denninger, Elke Giese: Textile and Model Lexicon. 8th, completely revised and expanded edition. Deutscher Fachverlag, Frankfurt am Main 2006, Vol. A – K, ISBN 3-87150-848-9 , p. 131.
  6. ↑ Anton Schenek: natural fiber lexicon . Deutscher Fachverlag, Frankfurt am Main 2001, ISBN 3-87150-638-9 , p. 63.
  7. ↑ a b This section is mainly based on: Frank Waskow: Hanf & Co. The renaissance of domestic fiber plants. Edited by the Catalysis Institute. Verlag die Werkstatt, Göttingen 1995, ISBN 3-89533-138-4 , pp. 119–124.
  8. ↑ Johann Michael Voit : Handbook of agricultural architecture: From the establishment and arrangement of stables, barns and apartments in general, then on composite agricultural buildings, farms, brewhouses, distilleries and other structures , Volume 1. Munich, 1825, p. 39f. Online google books
  9. ↑ This section is mainly based on: Frank Waskow: Hanf & Co. The renaissance of domestic fiber plants. Edited by the Catalysis Institute. Verlag die Werkstatt, Göttingen 1995, ISBN 3-89533-138-4 , pp. 124–126.
  10. ↑ Product description Blumenfeldmatte. Retrieved August 20, 2019 .
  11. ^ Alfred Halscheidt: Textiles from AZ . BoD - Books on Demand, 2011, p. 170; last accessed June 3, 2018.
  12. ↑ a b B. Mühlethaler, S. Haas: Strengths, hurdles and opportunities of natural insulation materials. In: Bauthema Naturdämmstoffe, 2006, ISBN 3-8167-6916-0 , pp. 9-10.
  13. ↑ a b W. Eicke-Hennig: Insulation materials made from waste paper or natural fibers - (not) an alternative? In: Building topic natural insulation materials. 2006, ISBN 3-8167-6916-0 .
  14. ^ W. Schneider: Ecologically building with renewable raw materials. In: Bauthema Naturdämmstoffe, 2006, ISBN 3-8167-6916-0 , p. 38.
  15. ↑ Michael Carus et al.: Study on the market and competitive situation for natural fibers and natural fiber materials (Germany and EU). Gülzower Expert Discussions 26, ed. from the specialist agency for renewable raw materials e. V., Gülzow 2008, p. 157. (without ISBN).
  16. ↑ Regulation (EU) No. 1007/2011 of the European Parliament and of the Council of September 27, 2011 on the names of textile fibers and the associated labeling and identification of the fiber composition of textile products and repealing Council Directive 73/44 / EEC and of Directives 96/73 / EC and 2008/121 / EC of the European Parliament and of the Council
  17. ↑ Michael Carus et al.: Study on the market and competitive situation for natural fibers and natural fiber materials (Germany and EU). Gülzower Expert Discussions 26, ed. from the specialist agency for renewable raw materials e. V., Gülzow 2008, pp. 15, 25, 33. (without ISBN).
  18. ↑ Michael Carus: Study on the market and competitive situation for natural fibers. 2008, p. 37ff.
  19. ^ Sustainable Economics.at : Fiber and dye plants from ecological cultivation ( Memento from September 27, 2007 in the Internet Archive ).
  20. ↑ Eliso Kvavadze et al .: 30,000-year-old Wild Flax Fibers. In: Science. Volume 325, 2009, p. 1359, doi: 10.1126 / science.1175404
  21. ^ Archaeologists discover oldest-known fiber materials used by early humans. eurekalert org from September 10, 2009.
  22. ↑ Early humans: Sewing with flax 34,000 years ago , scinexx.de accessed on December 11, 2012.
  23. ^ Ute von Reitzenstein: Flax in the 20th century from an ecological and economic point of view . ( Memento of October 21, 2007 in the Internet Archive ) - Technical work.
  24. ^ Village under the swastika, book accompanying the exhibition in the Hohenloher Freilandmuseum (2010).
  25. ^ Franz-Josef Sehr : The fire extinguishing system in Obertiefenbach from earlier times . In: Yearbook for the Limburg-Weilburg district 1994 . The district committee of the Limburg-Weilburg district, Limburg-Weilburg 1993, p. 151-153 .
  26. ^ "Henni Jaensch-Zeymer" hand weaving mill in Geltow
  27. ^ Heimatverein Wegberg-Beeck eV: Beecker flax museum
  28. ↑ Flachsbrechhütte Finsterlohr-Burgstall (on kelten-creglingen-finsterlohr.de).
  29. ↑ steinhuder-museen.de Steinhuder museums: fishing and weaving museum and toy museum
  30. ↑ Textile Museum St. Gallen (textilmuseum.ch) .