309 Ahmed El-Tantawi Methods of increasing the stretchiness of cotton fabrics Ahmed Ramadan Abd El Hamid Mohammed El-Tantawi. Faculty of Applied Arts, spinning weaving and knitting Department, Damietta University, [email protected] Abstract: Keywords: In response to getting more stretch and elasticity from 100% cotton fibers Stretch And Resilience as woven fabric not made from lycra or spandex yarns and so on. In this Properties survey, the researcher examines the relationship between different spinning Spinning Methods methods for Egyptian cotton using twill fabric structure under a variety of Average Float. weave factors on different weft densities to study the stretch and recovery from cotton fiber. The dependencies of the weft yarn spinning method and weft density were established. The effect of weave structure was determined. It founded that stress on the yarn will relax as a function of time due to the viscoelastic character of textile materials. The maximum wanted stretch direction will be limited to jamming in the anther direction. The max elasticity rate we get by increasing weft per cm for combed cotton but max resilience we can get at minimum weft per cm for carded cotton, Both max (elasticity& resilience) rates at same average float. The woven samples presented in this paper share three common design goals: low cost, stretchability, and long-running by comparing with their peers. Paper received 4th of January 2021, accepted 19th of February 2021, Published 1st of May 2021 weight before warp contraction, with 50% warp Introduction: (21) Not only actual behavior of fabric structure is density or less . precisely calculable but also geometry many Woven fabrics generally require the inclusion of features of the cloth are essentially dependent on special stretch yarns to provide them any the geometrical relationship. These fabric significant degree of stretch and recovery parameters are a tool for an innovative fabric comparing to knit fabrics. Even when currently designer in creating fabrics for diverse available specialty yarns are utilized to import applications; By studying well, the woven fabric stretch to woven fabrics, the fabrics provide less geometry will certainly provide simplified than optimal performance. For example, formulae to facilitate calculations and specific elastomeric yarns tend to expensive and don’t constants which are of value for cloth engineering, favorably stand the high temperatures used in problems of structure, and mechanical properties many textile manufacturing and treatment (2). operations, and their recovery doesn’t tend to be Initially., To design a cotton fabric having the very durable. Similarly, torque stretch yarns can optimum combination of proprieties for end-users, be used to achieve 15-20 % stretch in certain it is desirable if not essential to know how each of fabrics, but their recovery performance is only the proprieties in question is affected by changes marginal, they tend to be relatively expensive, and they tend to have a negative effect on the that can be made in the construction of the clothes. (7,24) The garment quality, appearance, and performance aesthetics of fabrics . are determined by fabric mechanical and surface Manufacturing processes designed to import proprieties mechanical stretch to woven fabrics have The most significant characteristic of textiles that generally been limited to those which apply some contributes to wearer comfort is stretch. Elastic length-wise tension while fabrics edges are not fibers (spandex/lycra) are commonly recognized stretched outwardly to any significant extent, however, such fabrics heretofore only achieve a as being used to offer stretch and recovery to (19) fabrics that are considered to provide the garment maximum stretch of about (12%) . with a dimension of comfort. (17). The beginning of the geometry of fabric has a Woven fabrics made from non-stretch yarns yet senior effect on their behavior, for example, the having high levels of stretch and recovery are weft dimensions decrease, and weft crimp described., The fabrics include about 50% of increases when the cloths are stretched in the warp synthetic fiber components and are woven such direction. In real fabrics the cross-sections of yarn the warp and filling are approximately balanced by significantly different for various fabrics. The This work is licensed under a Creative Commons Attribution 4.0 International License Methods of increasing the stretchiness of cotton fabrics 310 cross-section can be a circular, elliptical, race measuring strength value is normally pulled out by track, or any other shape. It all depends on the a suitable small tension in measuring linear weave float and packing of yam in the fabrics so density, and it can be removed by a pre-tension at that the cross-section of yarn can vary in different the start of the test, as this point was fabric proprieties. Pierce (18) suggest that textile conceptualized and investigated by; If a crimped yarns may be assumed to be perfectly elastic and fiber is inserted in the tester without any initial isotopic materials as they possess rigidity., Their tension, generalized load– elongation curve will resistance to bending affects the form of the yarn have the form shown in Fig.1. The origin of the in fabrics and has a marked effect on the balance curve may be put at A, where it diverges from the of crimp. Olofsson (17) assumed that yarn will take zero lines, but this point is difficult to locate shape produced by such forces and that cross yarn precisely. A better procedure is to put the origin at will flow into the available space. The yarn takes O, the extrapolated point corresponding to a up the shape of elastic being bent by point loads hypothetical straight fiber. The crimp is given by acting at the intersections. This assumption gives AO and may be expressed as a percentage of the valuable information on the inter yarn force, the initial length. Studies of the methods of measuring balance of crimp between warp and weft, and the and defining crimp have been made by [Betra. S. degree of setting (3). K., 1974] (3). The specimen’s crimp effects in stress value when Fig .1 Loads –elongation behavior of yarns. So that, the reason for this phenomenon a. Power or action stretch-fabric: this type discussed in this paper, this paper expects to find a indicates a high degree of extensibility and parameter for more stretch and recovery quick recovery. The stretch factor ranges here proprieties from 100% cotton yarns because there from 30% to 50% or more, Such kinds of exists a great need for methods of providing cotton stretch fabrics are suitable for knitwear, fabrics with stretch and recovery characteristics at athletic clothes. levels greater than heretofore achievable and it b. Comfort stretch-fabric applied to the fabrics will help in an appeal generation garment industry with less than (30-35) % stretch factor. Such for better understanding of the weaving process of fabrics are used for everyday clothing that cotton fabrics from both theoretical and practical needs only a conservative degree of elasticity point of view, it will decrease the cost of needed with stretch-fabric, comfort is achieved by of stretch and recovery characteristics of fabrics reducing garment containment imposed on especially in sportswear, non-wearable e-textiles, the body. These types of stretch fabrics are and medical textile, also it will be better for the suitable for outerwear garments as women’s proprietors of woven fabric, especially human skin slacks. proprieties ones. Other commercial classifications of Stretch In the literature, many studies deal with the Fabrics as (1-way, 2-way, and 4-way) Stretch performance properties of woven stretch fabrics. fabrics. (2-way) stretch fabrics have warp stretch As part of these studies, some studies investigate or weft stretch (some call them 1-way stretch the stretch fabrics: Stretch means to lengthen, fabrics). They are comfortable enough to wear, but widen, and distend for woven and knitted fabric they are not appropriate for garments such as (23). sports or athletic wear. Another feature of (2-way) As follows, there are two types of stretch fabric stretch cloth is that it doesn’t return to its original dependent on the degree of stretchability (10,22): shape. The term one-way stretch can also refer to May 2021 International Design Journal, Volume 11, Issue 3 311 Ahmed El-Tantawi knits and their percentage of stretch. It is a very viscoelastic properties of the fabrics above the low level, which means that such fabrics stretch yield point very little (0% - 25%)., (4-way) stretch fabrics can Senthilkumar Mani (21) in his paper present Figure extend in both directions – crosswise and (1) which indicate Loading and unloading longwise, which creates better elasticity and behavior of the fabric is almost curvilinear, which makes them perfect for sportswear. Stretch jersey is normally called as elastic deformation. Also, fabrics also have warp and weft stretch, because he compares the dynamic elastic behavior of they are knitted, not woven. All types mentioned cotton/spandex fabrics with 100% cotton fabrics above are made from (Lycra, spandex, and for Knitted Fabrics, It is found that the elastane), the names of the same synthetic fiber, cotton/spandex fabrics have higher dynamic work made of polymer- polyurethane rubber. recovery and lower stress value than that of cotton Stretch of fabrics measured in percentage, is fabrics for both wale wise and course wise defined as the ratio of elongated length and intimal directions., The cotton/spandex fabrics are length. Currently, fiber elongation values are preferable to cotton fabrics for dynamic elastic classified into five different categories (5): very low characteristics due to their quick work recovery (<5.0%), low (5.0-5.8) %, average (5.9-6.7) %, which enhances the power of the performance of high (6.8-7.6) %, very high elongation (>7.6%).