The starting point is always nature (the sun).
1. Among other substances, sunlight also causes dextrose to be formed in plants, the fundamental building block of the cellulose molecule.
2. Cellulose constitutes the fundamental structure of cotton plants, which are the source of cotton fiber.
3. Nutrients in food, which are transformed into chemical compounds, are the basis for the growth of wool and hair.
4. The silkworm collects a protein depot from its nourishment which is spun to endless threads through its glands.
5. After being treated with chemicals, the short fibers contained in the wood are transformed into an aqueous solution and then pressed through spinnerets. After drying, cellulosic fibers are obtained.
6. The raw materials for synthetic fibers generally stem from crude oil, which originates from the transformation of huge quantities of marine organisms.

The main difference between man-made fibers and natural fibers

In contrast to natural fibers, the composition and structure of man-made fibers can be determined by man. This lends polyester fibers special properties and renders them useful for many different purposes.

With the exclusion of ceramic or glass fibers, all man-made fibers, as well as natural fibers, are organic fibers.

Production of spin masses

To manufacture man-made fibers, viscous, stringy liquids are needed. The matter that results from dissolving or heating is called the spin mass. Today, three manufacturing processes are primarily used: polymerization, polycondensation, and poly-addition. The resulting spinnable matter from these processes is called a polymer.

Types of man-made fibres

As a rule, a distinction is made between man-made fibers from synthetic polymers and those from cellulosic polymers which both belong to the class of organic fibers. The ACRYLIC-, POLYAMIDE-, POLYESTER- and ELASTANE FIBRES belong to the man-made fibers made from synthetic polymers. In the case of man-made fibers manufactured from cellulosic polymers, the distinction is e.g. between the VISCOSE- and the ACETATE FIBRES.

Spinning process

To produce filaments (continuous yarns) from the spin mass, various spinning processes are employed: the dry spinning process, the wet spinning process, and the melt spinning process. In all cases, the spinnable material is pressed through the extremly small openings of a spinneret and upon exiting the spinneret the filaments produced are either gathered to a filament yarn and spooled, or joined to form tows. After spinning the man-made fibers the parallel alignment of the molecules is not yet optimal. Man-made fibers have to be drawn to acquire the ultimate properties for the yarns. The extent to which they are drawn depends on their intended use.

Forms of man-made fibers

The spin mass is pressed through the so-called spinnerets. Depending on the number of holes monofilaments (one hole) or multifilaments (several holes) are produced. Depending on the shape of the spinneret holes, different cross section shapes are obtained in the melt spun man-made fibers (from round, multi-lobed, triangular, star-shaped to ribbon-shaped). They exert a decisive influence on the properties of the textiles produced from them.

Texturing

Texturing is a procedure used to increase the volume and the elasticity of filament yarn. The essential properties of textured yarns and the products made from them are softness, fullness, a high degree of elasticity, thermal insulation, and moisture-transporting properties. All yarns which can be shaped by heat are suitable for texturing. The most important texturing processes are FALSE-TWIST TEXTURING, STUFFER-BOX TEXTURING, and AIR-JET TEXTURING.

Production of staple fibers

In all spinning processes, filaments are formed from the spin mass of the spinnerets. If the production of staple fibers is desired, i. e. short fiber sections for the spinning mill, thousands of filaments are combined to form tow and cut into staple fibers. While during the production of filament yarns each single filament bundle exiting the spinnerets is wound onto a spool, in the production of staple fibers numerous filament bundles are first combined to form a thick filament tow which can be crimped and cut into staple fibers. By cutting the tow, staple fibers are obtained which can be compared in length, e.g. with wool or cotton. Depending on the process used, the tow is either cut directly by the manufacturer and pressed into bales for delivery, or cut or torn into staple fibers using a so-called converter at a later stage by a downstream manufacturer.

Man-made fibers: Easier to care for, more economical, and better quality retention.

• Man-made fibers give dirt little chance.
• Man-made fibers save time, effort, and money.
• You get a more lasting pleasure from beautiful fabrics made from man-made fibers.

Polyester Fibers

The world leader among synthetic man-made fibers.

Polyester was one of the great man-made fiber discoveries of the forties and has been manufactured on an industrial scale since 1947. Polyester fibers are the first choice for apparel and are used in trousers, skirts, dresses, suits, jackets, blouses, and outdoor clothing.
Blends with cotton and virgin wool are very popular. They are often referred to as the “classical blend”. This is normally a combination of 55% polyester and 45% wool.
In the year 2013, 198,000 tons of polyester fibers were produced in Germany. This makes them the synthetic man-made fibers with the highest production figure.

Polyester fibers are produced by the melt spinning process. Raw materials are heated to a spinning mass, which is then pressed through spinnerets. Manufacturing techniques are now developed to the point where they can produce fibers adapted to suit the widest possible applications: they can have round, oval, or angular profiles, making them firm to the touch. They can be dull, bright, or glittery.

On care labels, polyester fibers are often given the abbreviation: “PES”.

Properties

Quality is much prized by processors and consumers.
Amongst the most important properties:
Polyester fibers are particularly resistant to light and weather and can withstand climatic effects.
They can be used where lightness and fineness are primary requirements.
Polyester fibers are very well suited to blends with natural fibers.
Fabrics in 100% polyester, or blends with an appropriately high proportion, are very crease-resistant and retain shape even when affected by moisture.
Polyester fibers have good moisture transport and dry quickly.
They are easy to care for.
High tenacity ensures above-average wear qualities.
Heat treatment results in permanent creases in trousers and skirts.

Source: Industrievereinigung Chemiefaser e.V.