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History of Carpet Yarn Materials. Lets talk a bit about the different manufacturing processes, materials, etc. Understanding carpets technically is always better, especially in contracts.
Over the past 50 years, the importance of various raw textiles for the home textiles industry has changed greatly. Up until the middle of the 20th century, the demand for textiles was met primarily using natural fibres. Today, natural products make up only about 12 % of fibres consumption for carpeting, while chemical fibres account for around 88 %. The various raw materials fall into the following categories:
Wool is the oldest and best known fibre for making rugs and carpets. The varieties and qualities are as varied as the names and breeds of their supplier, the sheep. The approximately 450 different breeds produce a wide variety of wool types, which are differentiated by country of origin. Only sturdy and robust wools are suitable for making carpets, and carpeting manufacturers select these very carefully. The high elasticity of wool provides for fast recovery, so that the appearance is uniform at all times. Thanks to its ability to absorb moisture without feeling damp to the touch, it helps to maintain a comfortable humidity in indoor environments.
The common belief that chemical fibres are a modern invention is not entirely accurate. As early as the 17th and 18th centuries, the English natural philosopher Robert Hooke and the French physicist Réamur published their ideas for producing “artificial silk”. However, it was not until the end of the 19th century that the Frenchman Count Chardonnet actually achieved this. At the Paris Exposition in 1884, he presented a fabric made of artificial fibres.
The first chemical copper rayon was spun in Germany in the last decade of the 19th century. Artificial acetate silks came to market shortly after the First World War. The history of synthetic fibre materials began on July 4th 1913. On this day, the German chemist F. Klatte, employed by “Chemische Fabrik Griesheim Elektron” applied for a patent for a method of producing fibres on the basis of the polymerization reaction of vinyl compounds. Initially, this invention had just as little practical application as the invention of the German Nobel laureate H. Staudinger, who created the first synthetic fibre in 1927, out of polyoxymethylene.
On July 3rd, 1931, the American chemical company Du Pont & de Nemours & Co applied for a patent for the production of polyamide fibres. A team of scientists, led by Dr. Wallace H. Carothers, succeeded in synthesizing what we today know as nylon, made out of hexamethyline diamine and adipinic acid in a form suitable for spinning. Du Pont brought this product to market in 1938 under the trade name Nylon 6.6.
In 1938, the German chemist Paul Schlack developed a further method for producing polyamide (patent application dated November 11 1938), using norleucine as his starting material. By heating lactam with hydrochloric acid, Schlack succeeded in obtaining a linear polyamide. The process did not violate the intellectual property rights of Du Pont and resulted in the production of Nylon 6, which was marketed under the trade name Perlon.
The numbers 6 and 6.6 indicate the number of carbon atoms in the respective polyamide components. “Poly” means many, and refers to the combination of small molecules to form bigger ones. To make polyamide yarn, the polymer is melted at approx. 250 °C and pressed into spinning nozzles. The thin, solidified strand pressed out of the nozzle is then stretched to many times its length, which creates a strong, extremely thin filament. Thicker yarn, that is required for making carpeting, consists of bundles of filaments. In texturing, the yarn is changed in a physical or chemical process from a smooth filament yarn to form Bulked Continuous Filaments (BCF), gaining the volume necessary for the manufacture of the carpeting. In addition to filament yarn, there are also spun fibre yarns. In this process, the spun threads are joined to form a cable, which is then stretched, crimped and cut to the desired length.
In the next step, these fibres are spun to make yarn. The main difference between spun fibre and filament yarns is that filament yarn consists of infinite filament bundles and spun-fibre yarn of short twisted and spun fibres (“stapled fibres”). By itself, the chosen fibre material is not always the optimum solution. By blending, it is possible to combine the advantages of one fibre with those of another. One of the most widely known blends is 80% wool with 20 % polyamide. Today, in addition to polyamide, manufacturers can also use the synthetics polyacrylic, polyester and polypropylene.
However, polyamide is by far the most important raw material for carpeting in all Western European countries.
Spinning is humankind’s oldest craft. Sculpture has been found in Asia Minor showing a woman spinning that dates back to the first millennium. Originally, a small band of fibres was drawn out of fibre material, wool and leaf fibres between the thumb and forefinger, and twisted and wound into thread by the turning of a spindle.
The first spinning wheel was built in 1530. The first carding machine for separating fibres was built by John Wyatt in 1736. In 1795, James Heargreaves designed the first spinning machine. In a spinning factory, the randomly ordered spinning fibres are first aligned in parallel and then processed into bands of fibres by means of a series of mechanical processes. The agglomerated fibres are opened in a series of matched opposing rollers and then passed downstream (carding engine).
The fibre bands are then cleaned of any impurities, drawn and at the same time, evened. The refined fibre band is transformed into spun fibre yarn through twisting (spinning machine), i.e. the parallel band of fibres is reinforced. This process gives rise to adhesion between the fibres, making the spun material more stable. By means of this process, the spinning fibres – mostly short and medium-length fibres – are spun into a relatively coarse, voluminous, fibrous yarn with a unique yarn character.
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