Fibre, natural

A fibre occurring in nature.
Note.. Fibres are found in all three sectors of the natural world, for example: animal (silk, wool); vegetable (cotton, jute); mineral (asbestos).(sub category of fibre)

Fibre, regenerated

A fibre formed from a solution of a natural polymer or of a chemical derivative of a natural polymer and having the same chemical constitution as the natural polymer from which the solution or derivative was made.(sub category of fibre)

Fibrets

Very short (<1mm) fine (diameter <50µ) fibrillated fibers that are highly branched and irregular resulting in very high surface area. Fibrets can be produced from a number of substances including acetate polyester nylon and polyolefins. By selection of polymer type and incorporation of additives they can be engineered to meet a range of specialized requirements.

Fibrids

Short irregular fibrous products made by mixing a dilute polymer solution with a nonsolvent with agitation. They can also be made by flash spinning and breaking up the resulting filaments. Used in felts in papermaking for filtration product etc. (Also see FIBRETS.)

Fibril

A tiny threadlike element of a synthetic or natural fiber.

Fibril-matrix bicomponent fibre

In this type, fine fibrils of one component are embedded in a matrix of the other. The individual fibrils are randomly distributed over the fibre cross-section, are of varying but very restricted length and do not extend along the full length of the fibre. As with the coresheath bicomponent fibre, this configuration is used to combine the properties of the two components. Matrix-fibril bicomponent fibres are sometimes known as 'biconstituent fibres' but the use of this term for this type of fibre is deprecated.( Sub Category of bicomponent fibre)

Fibrillated-Film Yarn

See SLIT-FILM YARN.

Fibrillating film

A polymer film in which molecular orientation has been induced by stretching to such a degree that it is capable of being converted into yarn or twine by manipulation, e.g., by twisting under tension or by rubbing laterally, which results in the formation of a longitudinally split structure (split fibre).

Fibrillating roller

A pinned roller used for fibrillation.

Fibrillation

The process of splitting a longitudinally oriented fibre, textile film or tape into a network of interconnected fibres. Fibrillation can also refer to a fibrillar failure of a fibre or film structure.
Note: Processes for producing fibrillation may be divided into two groups:
(i) those producing random splitting to give a relatively coarse network, e.g., by twisting or rubbing; and
(ii) those producing controlled splitting to give a relatively fine network, e.g., by rapidly rotating pinned rollers.

Fibrogram

A graph showing the length distribution of a sample of cotton fibres as determined using the Fibrograph instrument. Statistically it is the curve representing the second cumulation (integral) of the frequency distribution.(sub category of fibre length)

Fibroin

The part of a silk thread remaining after the gum has been discharged.

Fiddle string

A particular form of tight end (defect) or tight pick (defect) that becomes evident only after wet processing.

Figured casement

A casement cloth in which a pattern has been introduced by weaving.

Figured fabric

A fabric in which patterns or motifs are produced by a combination of distinct weaves usually requiring a dobby or jacquard mechanism.