Flax, Linen
8-15 usd/kgFlax is a bast fibre, like hemp and jute, which is extracted from the stalk of the blue-flowered flax plant grown for its seeds (linseed) and fibre. As a natural material, its properties will vary widely, depending on the plant, growing conditions and where in the stalk the fibre came from. Even so, flax and the other bast fibres have impressive qualities. As a technical fibre it competes alongside manmade fibres like glass (GF) and aramid (AF) in terms of strength to weight. And as linen fabric – thought to be one of the oldest textiles – used for clothing and interiors, flax is prized for its high strength, soft hand and high lustre. In addition, it gets stronger when wet, and can soak up around 20% moisture before feeling damp.
Flax is widely cultivated and grows without much need for fertiliser, pesticide or herbicide. Once harvested, the stems require retting to release the fibres from their bundles. This is typically carried out by lying them in water or in the field where they were grown. Microbes breakdown the hemicellulose-pectin matrix that locks the fibres in.
Yarn production involves decorticating and combing the fibres (this is also known as scutching and hackling when carried out by hand) to produce a sliver free from contamination; bleaching; drying; spinning; and winding. Of course, for natural colour fibres, some of these processes are avoided.
Nothing is wasted in production. The seeds are used for food (linseed oil comes from another type of flax plant), the woody core of the stem goes into particleboard or mycelium materials (fungi), and the short fibres are converted into paper or board.
High quality flax used to make linen textiles and clothing is soft, fine and strong. It is often used in bedding, towels and warm weather clothing, because it can gain up to around 20% moisture without feeling damp. Often compared to cotton, flax is superior in many ways. However, the processes used to extract the fibre make it more expensive – typically around twice the price for equivalent quality. It is also more variable, and this unpredictability does not lend itself so well to modern mass production. However, it is much less damaging to the environment.
Fibre ranges from coarse to fine, and the price depends a great deal on quality. Flax fibre consists of nodes, also called slubs, which are lumps along its length that act as dislocations. They decrease strength and increase flexibility. The finest and most expensive linen is free from visible nodes, with a consistent diameter along its length.