Nonwovens Glossary - INDA

Ff
Fabric
A sheet structure made from fibers, filaments or yarns.
Face area
The area of a media used in air or liquid filters.
Facing
An outer covering of a product that is exposed during use or is placed against the body.
Fan
A device using blades for moving or producing artificial currents of air.
Felt (Nonwoven definition)
A sheet of matted fibers, most often wool or fur, bonded together by needlepunch and/or
chemical processes and the application of moisture, heat and pressure.
Felt (Textile definition)
A woven fabric, generally made of wool, heavily shrunk or “fulled” by a combination of
moisture, heat, chemicals and pressure so as to make it almost impossible to distinguish the
weave.
Fiber
A unit of matter characterized by a high ratio of length-to-width. Material which can be spun
into yarn or made into fabric by interlacing (weaving), interlooping (knitting), or interlocking
(bonding). Discontinuous fibers are referred to as “staple fibers” with lengths designated in
inches or millimeters. Typical textile fibers have length-to-width ratios in the order of 1000 to
1, are longer than one inch, have diameters greater than 10 microns, and mass-per-unit-length
(linear density) values in the order of one gram per thousand meters.
Fiber distribution
In a web, the orientation (random or parallel) of fibers and the uniformity of their
arrangement.
Fiber variant
A man-made fiber type derived through the use of additives or modification of the polymer
chemistry or fiber surface. Fiber variants exhibit or emphasize specific properties and are
intended for focused end-uses or specialized applications. The modification may consist of
adding end or side groups to the fiber forming polymer, altering spin finish, changing
spinneret geometry, or varying any combination of controllable manufacturing parameters.
22 Nonwovens Glossary