NAP: A downy surface given to a cloth when part of the fiber is raised from the basic structure.
NAPHTHALENE: A solid aromatic hydrocarbon (C10H8) derived from coal tar. Naphthalene is used as moth flakes and as the basis of certain dye components.
NAPHTHOL DYES: See DYES.
NAPPING: A finishing process that raises the surface fibers of a fabric by means of passage over rapidly revolving cylinders covered with metal points or teasel burrs. Outing, flannel, and wool broadcloth derive their downy appearance from this finishing process. Napping is also used for certain knit goods, blankets, and other fabrics with a raised surface.
NARROW FABRIC: Any nonelastic woven fabric, 12 inches or less in width, having a selvage on either side, except ribbon and seam binding.
NATURAL FIBER: A class name for various genera of fibers (including filaments) of: (1)
animal (i.e., silk and wool); (2) mineral (i.e., asbestos); or (3) vegetable origin (i.e., cotton, flax,
jute, and ramie).
- The sudden reduction in the diameter of an undrawn manufactured filament when it is stretched.
- Narrowing in width of a fabric or film when it is stretched.
- A thin, metal device, usually with an eye at one end for inserting the thread, used in sewing to transport the thread.
- The portion of a knitting machine used for intermeshing the loops. Several types of knitting needles are available. (Also see SPRING NEEDLE and LATCH NEEDLE.)
- In nonwovens manufacture, a barbed metal device used for punching the web’s own fibers vertically through the web.
NEEDLE BED: Flat metal plate with slots at regular intervals in which the knitting needles slide on the knitting machine.
NEEDLED FABRICS: The product of the needle loom (q.v.). Needled fabrics are used for rug pads, papermaker’s felts, padding, linings, etc.
NEEDLE LOOP: A loop of yarn drawn through a loop made previously.
NEEDLEPUNCHING: The process of converting batts or webs of loose fibers into a coherent nonwoven fabric on a needle loom (q.v.).
NEEDLE SET-OUT: A term that refers to long periods of time when certain needles are removed from the knitting cycle. The process is used to make sweater cuffs.
NEEDLE SLOT: A groove that houses a needle in the cylinder or dial of a circular-knitting machine or the needle bed of a flat-bed machine.
NEP: A small knot of entangled fibers that usually will not straighten to a parallel position during carding or drafting.
NET RATE: In a fiber production process the total throughput less waste and inferior or off-grade material.
NETTING: The process of knotting threads into meshes that will not ravel.
NEUTRON-ABSORBING FIBER: Polyethylene fiber modified with boron used in the nuclear industry for reducing neutron transmission.
NINON: A lightweight fabric of silk or manufactured fibers made in a plain weave with an open mesh. Used for curtains and evening wear.
- The line or area of contact between two contiguous rollers.
- A defect in yarn consisting of a thin place.
NIP CREASES: Creases occurring at regular intervals along a fabric selvage subsequent to a nipping operation such as calendering or padding. Such creases are caused by a loosely wound selvage or improper let-off tension which allows the fabric to fold over or gather at the selvage prior to entering the nip of the rolls.
NOIL: A short fiber that is rejected in the combing process of yarn manufacture.
NONELASTIC WOVEN TAPE: A woven narrow fabric, weighing less than 15 ounces per square yard, made principally of natural and/or manufactured fibers, including monofilaments, but not containing rubber or other similar elastic stands.
NONTORQUE YARN: See TEXTURED YARNS.
NONWOVEN FABRIC: An assembly of textile fibers held together by mechanical interlocking in a random web or mat, by fusing of the fibers (in the case of thermoplastic fibers), or by bonding with a cementing medium such as starch, glue, casein, rubber, latex, or one of the cellulose derivatives or synthetic resins. Initially, the fibers may be oriented in one direction or may be deposited in a random manner. This web or sheet of fibers is bonded together by one of the methods described above. Normally, crimped fibers that range in length from 0.75 to 4.5 inches are used.
Nonwoven fabrics are used for expendable items such as hospitable sheets, napkins, diapers, wiping cloths, as the base material for coated fabrics, and in a variety of other applications. They can also be used for semi-disposable items and for permanent items such as interlinings.
NOVELTY YARN: A yarn produced for a special effect. Novelty yarns are usually uneven in size, varied in color, or modified in appearance by the presence of irregularities deliberately produced during their formation. In singles yarns, the irregularities may be caused by inclusion of knots, loops, curls, slubs, and the like. In plied yarns, the irregularities may be effected by variable delivery of one or more yarn components or by twisting together dissimilar singles yarns. Nub and slub are examples of novelty yarns.
NOVOLOID FIBER: A manufactured fiber containing at least 85% by weight of a cross-linked novolac (FTC definition). Novoloid is flame resistant and nonmelting. Its primary use is in flame-protective garments and products.
- The spout through which something is discharged, i.e., oil in finish application or fibers in web laying.
- A term sometimes used to refer to spinnerets.
NUB YARN: A novelty yarn containing slubs, beads, or lumps introduced intentionally.
NUCLEATION: A process by which crystals are formed. Crystals form initially on minute traces of foreign substances that act as the nucleus, then grow by external addition.
NUN’S VEILING: A soft, lightweight, plain-weave fabric that usually comes in black and white, nun’s veiling is a rather flimsy, open fabric but always of high quality. It may be made from fine woolen yarn or yarns spun from manufactured fibers such as nylon, acrylic, or polyester.
NYLON FIBER: A manufactured fiber in which the fiber forming substance is any long chain synthetic polyamide having recurring amide groups (-NH-CO-) as an integral part of the polymer chain (FTC definition). The two principal nylons are nylon 66, which is polyhexamethylenedianime adipamide, and nylon 6, which is polycaprolactam. Nylon 66 is so designated because each of the raw materials, hexamethylenediamine and adipic acid, contains six carbon atoms. In the manufacture of nylon 66 fiber, these materials are combined, and the resultant monomer is then polymerized. After polymerization, the material is hardened into a translucent ivory-white solid that is cut or broken into fine chips, flakes, or pellets. This material is melted and extruded through a spinneret while in the molten state to form filaments that solidify quickly as they reach the cooler air. The filaments are then drawn, or stretched, to orient the long molecules from a random arrangement to an orderly one in the direction of the fiber axis. This drawing process gives elasticity and strength to the filaments.
CHARACTERISTICS: Although the properties of the nylons described above vary in some respects, they all exhibit excellent strength, flexibility, toughness, elasticity, abrasion resistance, washability, ease of drying, and resistance to attack by insects and microorganisms.
END USES: Nylon is used for apparel such as stockings, lingerie, dresses, bathing suits, foundation garments, and wash-and-wear linings; for floor coverings; for tire cord and industrial fabrics; and in-home furnishings such as upholstery fabrics.
NYTRIL FIBER: A manufactured fiber containing at least 85% by weight of a long chain polymer of vinylidene dinitrile [-CH2-C(CN)2-] and having the vinylidene dinitrile group in no less than every other unit in the polymer chain (FTC definition). Nytril fibers have a low softening point so they are most commonly used in articles that do not require pressing such as sweaters and pile fabrics. They are also blended with wool to improve shrink resistance and shape retention.