Weft-knitted fabrics

The goods may be solvent scoured in rotary drum machine, restricting the load to 50% of the machine maximum capacity and the centrifuging time to 1 min to avoid the formation of pressure creases. Warp knitted fabrics are, in general, more stable to tension than weft knitted fabrics. 

There are two types of knitted fabrics, both of which are important for sport apparel applications weft-knitted fabrics (Figure 5.3) and warp-knitted fabrics (Figure 5.4). 

In this chapter, we will address the class of sport garments made of weft-knitted fabrics as being more flexible in production change, comparatively small minimums in production quantities, possessing more extensive structural capabilities and also widely used in seam-free sportswear. 

Ramakrishna S. Characterization and modeling of the tensile properties of plain weft-knit fabric-reinforced composites. Compos Sci Tech 1997 57 1-22. 

Wang Y, Gowayed Y, Kong X, Li J, Zhao D. Properties and analysis of composites reinforced with E-glass weft-knitted fabrics. J Compos Tech Res 1995 17 283-8. 

Rios CR, Ogin SL, Lekakou C, Leong KH. A study of damage development in a weft knitted fabric reinforced composite part 1 - experiments using model sandwich laminates. Compos Appl Sci Ma /2007 38(7) 1173-793. 

Because they are capable of being produced in seamless tubular form, weft-knitted fabrics provide, in theory, an attractive and economic alternative to both woven and needled constructions. By inlaying appropriate yams into the knitted stracture, the elasticity normally associated with such fabrics can also be controlled and may be used to enhance the particle collection capability. On the down side, in critical appU-cations, the filtration efficiency will be inferior to a nonwoven constmction and further problems are likely to be found in respect of the large number of sleeve diameters which the industry requires. Limitations are also inevitable in respect of the number of physical and chemical finishes that are frequently administered to both woven and nonwoven constmctions. 

Various fabric stmctures are currently used to provide resistance against stabs and slashes. They include tightly woven stmctures, woven and nonwoven composites/lam-inates, as well as warp- and weft-knitted fabrics. 

Since para-aramid yam is the most widely used yam in cut resistance fabrics, ring spun staple fibre aramid yams were chosen to be used in one face of the weft-knitted fabric. A composite yam had to be used for the other face of the fabric. It is imperative that the most suitable yams for each face of the fabric are chosen. 

X. Li, and S. Bai, Sheet forming of the multy-layered biaxial weft knitted fabric reinforcement. Part 1 On hemispherical surfaces. Compos. A 40, 766-777 (2009). 

Barre lbar [Fr, fr. ML barra] (1936) n. A defect characterized by bars or streaks, fill-ingwise in woven fabrics or coursewise in weft-knit fabrics, caused by uneven tension in knitting, defective yarn, improper needle action, or other similar factors. 

Circular-knit fabric n. A tubular weft-knit fabric made of a circular-knitting machine. 

Weft-knit fabric (1943) n. See circular-knit fabric and flat-knit fabric. 

Schematics illustrating the structures of (a) plain weave fabric, (b) weft-knitted fabric and (c) warp-knitted fabric. 

Comparison of the general nature of the stress-strain properties found in woven, warp-knitted and weft-knitted fabrics. 

Kurbak A and Soydan A S (2008), Basic studies for modeling complex weft knitted fabric structures. Part III A geometrical model for 1x1 purl fabrics . Text Res 7,78(5), 377-381. 

Schwarz, A., 2003. Comparison of the mechanical properties of woven, warp knitted and weft knitted fabrics with regard to their structural composition (Bachelor thesis). Niederrhein University of Applied Sciences, Monchengladbach. 

The key feature of circular weft knitting is to produce fabric structures in a tubular form. Figure 6.5 shows a tubular weft-knitted fabric developed for vascular stent application on a circular weft knitting machine with a small-diameter cylinder. The diameter and stitch density of a tube can be adjusted by varying the cylinder diameter and machine gauge, respectively. 

Figure 6.5 A tubular weft-knitted fabric by circular weft knitting.

Cherif C, Krzywinski S, Diestel O, Schulz C, Lin H, Klug P, et al. Development of a process chain for the realization of multilayer weft knitted fabrics showing complex 2D/3D geometries for composite applications. Text Res J 2012 82 1195-210. 

A. Asayesh, M. Maroufi, Effect of yam twist on wicking of cotton interlock weft knitted fabric, Ind. J. Fibre Text. Res. 32 (2007) 373-376. 

Cebulla, H., Diestel, O., Offerman, P., March 2002. FuUy fashioned biaxial weft knitted fabrics. Autex Research Journal 2, 8—13. 

The Yeh Group, which produces both warp and weft knitted fabrics, says it will be the first textile manufacturer to implement a new waterless dyeing process developed by DyeCoo Textile Systems of the Netherlands which is currently being readied for commercial introduction in the fourth quarter of this year. The company says it has exclusive rights to the process and is branding fabrics produced using it as DryDye fabrics. 

Knitted structures are made of loops of yam interconnected with each other. The size of the loop can be altered to produce a fabric as per required characteristics. Some knitted stmctures offer robusmess and are suitable for many technical applications. Knitted stmctures are mainly classed as weft knitted or warp knitted. Weft-knitted fabrics are highly stretchable and hence are extremely useful for undergarment and sportswear production. Warp-knitted fabrics do not unravel as easily as weft-knitted stmctures, and have significant insulating properties. In piezoelectric harvesting textiles, knitted stmctures offer extensibility, which is advantageous for wearable piezoelectric textiles, allowing wearer comfort. 

Flat Knit Fabric n (1) A fabric made on a flat-knitting machine, as distinguished from tubular fabrics made on a circular-knitting machine. While tricot and mil-anese warp-knit fabrics (non-run) are knit in flat form, the trade uses the term flat-knit fabric to refer to weft-knits fabrics made on a flat machine, rather than warp-knit fabrics. (2) A term used in the underwear trade for plain stitch fabrics made on a circular-knitting machine. These fabrics have a flat surface and are often called flat-knit fabrics to differentiate them from ribbed-knit or Swiss rib fabrics. In this case, the term refers to the texture, not the type of machine on which the fabric was knit (Kadolph SJJ, Langford AL (2001) Textiles. Pearson Education, New York Vincenti R (ed) (1994) Elsevier s textile dictionary. Elsevier Science and Technology Books, New York). 

Weft-Knit Fabric n (1943) See Circular-Knit Fabric. 

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