Synthetic fibres[edit] Artificial fibres can be made by extruding a polymer, through a spinneret (polymers) into a medium where it hardens. Wet spinning (rayon) uses a coagulating medium. In dry spinning (acetate and triacetate), the polymer is contained in a solvent that evaporates in the heated exit chamber. In melt spinning (nylons and polyesters) the extruded polymer is cooled in gas or air and then sets.[4] Some examples of synthetic fibers are polyester, rayon, acrylic fibers and microfibers. All these fibres will be of great length, often kilometres long. Synthetic fibers are more durable than most natural fibers and will readily pick-up different dyes. Artificial fibres can be processed as long fibres or batched and cut so they can be processed like natural fibre. Natural fibres[edit] Sheep, goats, rabbits, silkworms, and other animals, as well as minerals like asbestos, are sources of natural fibers (cotton, flax, sisal). These vegetable fibers can originate from the seed (cotton), the stem (bast fibres: flax, hemp, jute), or the leaf (sisal). All of these sources require a number of steps, each of which has a distinct name, before a clean, even staple is produced. All of these fibers, with the exception of silk, are short, only a few centimeters long, and have a rough surface that allows them to adhere to other like staple fibers.