The extent of crimped fibre substantially freed from external restraint, and measured with respect to its general axis of orientation.
b) Fibre Extent
The distance in a given direction between two planes (each perpendicular to the given direction) that just enclose the fibre without intersecting it.
1. If the fibre is in a sliver (q.v.) (or yarn, roving, etc.) and the direction of the extent is not specified, the "given direction" is to be taken as the axis of the sliver.
2. It should be noted that the extent of a fibre is a variable property that differs from the straightened length of the fibre according to circumstances; thus in a card web, the example, where the fibres are in a state of considerable disarray, the extent of a fibre after it has been passed through one or more drawing processes. If, for any reason, a fibre is subject to a stretching force, its extent in the direction of the force may be greater than its straightened length.
c) Staple Length
A measurement by which a sample of fibrous raw material is characterised according to its technically most important fibre length.
The staple length of wool is usually taken as the length of the longer fibres in a hand-prepared tuft or "staple" in its naturally crimped and wavy condition (see crimp). In cotton, on the other hand, the staple length corresponds very closely to the modal or most frequent length of the fibres when measured in a straightened condition.