Coir

Coir (/ˈkɔɪər/), also called coconut fibre, is a natural fibre extracted from the outer husk of coconut, and used in products such as floor mats, doormats, brushes, and mattresses. Coir is the fibrous material found between the hard, internal shell and the outer coat of a coconut. Other uses of brown coir (made from ripe coconut) are in upholstery padding, sacking and horticulture. White coir, harvested from unripe coconuts, is used for making finer brushes, string, rope and fishing nets. It has the advantage of not sinking, so can be used in long lengths in deep water without the added weight dragging down boats and buoys.

Coir must not be confused with coir pith, which is the powdery and spongy material resulting from the processing of the coir fibre. Coir fibre is locally named 'coprah' in some countries, adding to confusion. Pith is chemically similar to coir, but contains much shorter fibers. The name coco peat may refer either to coir or the pith or a mixture, as both have good water-retaining properties as a substitute for peat.

The name coir originally comes from the Tamil கயிறு (kayiru), and later the Malayalam word കയർ (kayar), for cord or rope (traditionally, a kind of rope is made from the coconut fibre). Ropes and cordage have been made from coconut fibre since ancient times. The Austronesian peoples, who first domesticated coconuts, used coconut fibre extensively for ropes and sennit in building houses and lashed-lug plank boats in their voyages in both the Pacific and the Indian Oceans. Polynesians themselves grew a special type of coconut called the niu kafa which yields a lot more fibre per fruit than types grown for human consumption (niu vai, for their water).

Later Indian and Arab navigators who sailed the seas to Malaya, China, and the Persian Gulf centuries ago also used coir for their ship ropes. Arab writers of the 11th century AD referred to the extensive use of coir for ship ropes and rigging.

A coir industry in the UK was recorded before the second half of the 19th century. During 1840, Captain Widely, in co-operation with Captain Logan and Thomas Treloar, founded the known carpet firms of Treloar and Sons in Ludgate Hill, England, for the manufacture of coir into various fabrics suitable for floor coverings.

Coir fibres are found between the hard, internal shell and the outer coat of a coconut. The individual fibre cells are narrow and hollow, with thick walls made of cellulose. They are pale when immature, but later become hardened and yellowed as a layer of lignin is deposited on their walls.

Each cell is about 1 mm (0.04 in) long ^{[citation needed]} and 10 to 20 μm (0.0004 to 0.0008 in) in diameter. Fibres are typically 10 to 30 centimetres (4 to 12 in) long. The two varieties of coir are brown and white. Brown coir harvested from fully ripened coconuts is thick, strong and has high abrasion resistance. It is typically used in mats, brushes and sacking. Mature brown coir fibres contain more lignin and less cellulose than fibres such as flax and cotton, so are stronger but less flexible. White coir fibres harvested from coconuts before they are ripe are white or light brown in color and are smoother and finer, but also weaker. They are generally spun to make yarn used in mats or rope.

The coir fibre is relatively waterproof, and is one of the few natural fibres resistant to damage by saltwater. Fresh water is used to process brown coir, while seawater and fresh water are both used in the production of white coir.