Textile yam

Cybulska M, Goswani B C and MacAlister D III, Failure mechanism in staple yams . Textile Research Journal, 2001,71, 1087-1094. 

Pouresfandiari F, Fushimi S, Sakaguchi A, Saito H, Toriumi K, Nishimatsu T, et al. Spinning conditions and characteristics of open-end rotor spun hybrid yams. Textil Res J 2002 72(l) 61-70. 

Abbott GM. Force-extension behavior of helically wrapped elastic core yams. Textil Res J 1984 54 204-23. 

Shin HS, Erlich DC, Simons JW, Shockey DA. Cut resistance of high-strength yams. Textil ResJ 76) 601. 

Bashir, T., et al., July 2013. Stretch sensing properties of conductive knitted structures of PEDOT-coated viscose and polyester yams. Textile Research Journal 84 (3), 323—334. 

A similar conclusion of good performance of pure stainless steel filament yam textile electrodes has also been reported in medical applications [27]. Additionally, the pure stainless steel filament yam electrodes are more robust and could withstand many cyclings of charge and discharge compared to the silver-coated yarn electrodes. The sUver-coated PBO filament yam electrode devices yielded before the stainless steel filament yam electrode devices. 

Due to the physical binding of yams, textile stractures demonstrate good tensile recovery and shear properties, superior conformability, excellent skin contact (especially with knitted stmctures), breathability and comfort. As such, textile structures will provide an excellent platform for creating smart wearable systems. 

The physical, chemical, and mechanical properties of yams are characterized in methods similar to those used for fibers. To describe the fineness of the yam, textile engineers often use the unit tex, which is the weight in grams of a kilometer of yam, or decitex, which is a finer measurement corresponding to the weight in grams of 10km of yam. Many other units have been used over time by different industries. 

Kamath, Y.K. S.B. Hornby, H.D. Wiegmann, and M.E. Wilde. 1994. Wicking of spin finishes and related liquids into continuous filament yams. Textile Res. J., 64(1)33-40. 

Cross-sectional area or fiber fineness also affects textile processing efficiency and the quatity of the end product. The number of fibers in a cross section of yam of a given size is related to fiber fineness, that is, the smaller the fiber cross section the more fibers will be needed in the yam. Other factors being equal, yam strength increases as the number of fibers in the yam cross section increases. However, fibers with too small a cross section caimot be processed efficiently. 

Typical textile fibers have linear densities in the range of 0.33—1.66 tex (3 to 15 den). Fibers in the 0.33—0.66 tex (3—6 den) range are generally used in nonwoven materials as well as in woven and knitted fabrics for use in apparel. Coarser fibers are generally used in carpets, upholstery, and certain industrial textiles. A recent development in fiber technology is the category of microfibers, with linear densities <0.11 tex (1 den) and as low as 0.01 tex. These fibers, when properly spun into yams and subsequendy woven into fabrics, can produce textile fabrics that have excellent drape and softness properties as well as improved color clarity (16). 

B. C. Goswami, J. G. Martindale, and E. L. Scardino, Textile Yams Technology, Structure and ApplicationsAm. Wiley Sons, Inc., New York, 1977. 

E. R. KasweU, Textile Fibers, Yams, andFabrics, Reinhold Publishing Corp., New York, 1953, p. 57. 

Spandex Fibers. Spandex fibers are suppHed for processing into fabrics in four basic forms as outlined in Table 3. Bare yams are suppHed by the manufacturer on tubes or beams and can be processed on conventional textile equipment with the aid of special feed and tension devices. In covered yams, the spandex fibers are covered with one or two layers of an inelastic filament or staple yam the hard yam provides strength and rigidity at full extension, which faciUtates knitting and weaving. 

Jets for continuous filament textile yam are typically 1 cm diameter gold—platinum ahoy stmctures with 20—500 holes of 50—200 p.m diameter. Tire yam jets are also 1 cm in diameter but typicahy use 1000—2000 holes to give the required balance of filament and yam denier. Staple fiber jets can have as many as 70,000 holes and can be made from a single dome of ahoy or from clusters of the smaller textile or tire yam jets. The precious metal ahoy is one of the few materials that can resist the harsh chemical environment of a rayon machine and yet be ductile enough to be perforated with precision. Glass jets have been used for filament production, and tantalum metal is a low cost but less durable alternative to gold—platinum. 

Asahi Chemical Industries (ACl, Japan) are now the leading producers of cuprammonium rayon. In 1990 they made 28,000 t/yr of filament and spunbond nonwoven from cotton ceUulose (65). Their continuing success with a process which has suffered intense competition from the cheaper viscose and synthetic fibers owes much to their developments of high speed spinning technology and of efficient copper recovery systems. Bemberg SpA in Italy, the only other producer of cuprammonium textile fibers, was making about 2000 t of filament yam in 1990. 

Since the early 1980s, the viscose-based staple fibers have, like the cuprammonium and viscose filament yams in the 1970s, ceased to be commodities. They have been repositioned from the low cost textile fibers that were used in a myriad of appUcations regardless of suitabUity, to premium priced fashion fibers dehvering comfort, texture, and attractive colors in ways hard to achieve with other synthetics. They are stiU widely used in blends with polyester and cotton to add value, where in the 1980s they would have been added to reduce costs. 

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