China
Africa
Explore chapters and articles related to this topic
Textile Finishing
Published in Tom Cassidy, Parikshit Goswami, Textile and Clothing Design Technology, 2017
Andrew J Hebden, Parikshit Goswami
Heat setting involves achieving dimensional stability of a fabric (or yarn) that has a thermoplastic component. During the fabric-manufacturing process, the textile is exposed to processes such as drawing, spinning, knitting, or, indeed, one or more of the finishing treatments outlined in this chapter. As a result, significant stress is created within the fibers of the fabric, and thus, when the material is subjected to subsequent heat treatment (e.g., ironing) or laundering, relaxation of the fibers takes place, and this can be observed as shrinkage or a change of shape in the garment.2,3 It is thus desirable to heat set the textile in advance to reduce this effect for the consumer. During such a treatment, the melting point of the polymer must not be exceeded, but sufficient energy must be supplied to break interchain bonds, and this leads to an observable decrease in tensile strength. The typical setting temperatures for some common textiles are included in Table 13.1.
Dyes and Auxiliaries for Textile Printing
Published in Asim Kumar Roy Choudhury, Principles of Textile Printing, 2023
All of these fibers are thermo-plastic; the fibers soften instead of decomposing or igniting when exposed to sufficient heat. Unless the material is heat-set, it will shrink and creases will form during hot aqueous treatments, such as dyeing or steaming/heat treatment after printing. In order to make the material dimensionally stable, heat-setting may be carried out in a medium of hot air, steam or hot water. The materials are also to be scoured and bleached, if necessary.
Future trends
Published in Rajkishore Nayak, Saminathan Ratnapandian, Care and Maintenance of Textile Products Including Apparel and Protective Clothing, 2018
Rajkishore Nayak, Saminathan Ratnapandian
Crease-resist garments have been in use for quite some time. The use of resins and cross-linking agents is well established for cotton and its blends. In the case of synthetics, especially polyester, heat-setting techniques have been well-researched. These finishes have to be taken into consideration while preparing care labels.
Effects of stabilising overfeed on the properties of draw textured polyester yarns
Published in The Journal of The Textile Institute, 2023
Bibekanada Basu, Subhankar Maity
False twist texturing process is the most widely used texturing process for bulking manmade filament yarns. Generally, unoriented filament yarns were conventionally used as the starting material for the texturing process, but such yarns are highly unstable (Warwicker, 1978). Therefore, nowadays, partially oriented yarn (POY) is used as a starting material. The POY is stable enough to be used in the simultaneous draw texturing (SDT) process within a few months of manufacture (Warwicker, 1978). Moreover, the POY is produced with a relatively higher production speed, resulting in economic savings. In the SDT process, drawing is applied to the starting POY yarn at the same time as imparting false twist while the yarn is passing over the heater of a texturing machine at a controlled temperature. A Double Heater Draw Texturing machine was introduced by Stoddart & Seem in the mid of 1950, which had a primary heater and a secondary heater (Figure 1) (Sengupta & Gulrajani, 1979). In this machine, the twist is imparted into a pre-oriented yarn while running continuously through the heaters. The reversal of twist in the yarn, while the yarn is still in a plastic state from heating, will develop the necessary bulkiness and texture to the resulted yarn (Atkinson, 2012). The role of the heaters is to stabilise the textured structure of the yarn after arriving at glass transition temperature. Thus, the yarn structure is undergone a permanent change at the molecular level. The yarn coming out from the primary heater is known as crimped yarn or stretched yarn, whereas, after the secondary heater it is known as textured yarn. The degree of texturing depends on amount of allowable yarn shrinkage and resident time of the yarn in the heater zones. The stabilising overfeed (SOF) is a deciding factor of residence time and adjusting criticality between the yarn shrinkage within the secondary heater and that of tension control between intermediate roller and output roller (Figure 1) (Hearle et al., 2001). Thus, the role of the secondary heater is to heat setting of the yarn. The objectives of heat setting are to improve dimensional stability, mitigate shrinkage, decrease crease resistance, increase elasticity and resiliencies of resultant fabric (Miller & Murayama, 1984).
Wrinkle free plaited knitted fabrics without pre-heat setting
Published in The Journal of The Textile Institute, 2018
Tariq Mansoor, Hafiz Faisal Siddique, Azam Ali, Petra Komarkova, Antonin Havelka, Zahid Hussain
The primary objective of heat setting operation is to dimensionally stabilize the fabrics when contain thermoplastic fibers. These fabrics may cause shrinkage, wrinkled, or distorted during wet processing or in the consumer’s hands. The heat setting is a way to reduce or eliminate these undesirable properties (Tomasino, 1992). Heat setting process is a key step for achieving the desired properties (width, weight, stretch, and power, etc.) in fabrics. Furthermore, heat setting also reduces the effect of creasing up to some extent (Meredith, 1971). Elastic-knitted fabrics in gray stage are relaxed and further the fabric is heat set, bleached, dyed, and compacted in the wet processing treatment. Heat setting process is the key step to lock the desired fabric properties like width, weight, stretch, and power (Meredith, 1971; Senthilkumar, Anbumani, & Hayavadana, 2011). There are many ways of heat setting i.e. contact (dry), steam, hydro, etc. (Karmakar, 1999). Dry heat setting of filament fabrics is considered in relation to dimensional stability, wet creasing, stiffness and recovery from dry creasing, and dyeing properties. Wet processing of knitted fabrics often causes distortions in the fabrics like creases and wrinkles. In knitted fabric, all types of shrinkage take place when the moisture content is below 50%, the loop length is only main factor influencing the dimensional properties of the knitted fabrics (Marvin, 1954). (Patil, Raichurkar, Kulkarni, Patil, & Sayyed, 2011; Ziko, 2015). The increase of draw ratio in the elastane plaiting yarn leads to an increase in dimensional change, stitch density, fabric weight, and wrinkle effect (Uçar, Karakaş, & Şen, 2007). Heat setting is also used as treatment by which crease resistance, resilience, shape retention, and elasticity are imparted to the fibers. It also brings changes in softness, stretch ability, strength, dye ability, and sometimes on the color of the material (Karmakar, 1999). It also removes any creases, improves shrinkage resistance, guarantees level dyeing, and improves the fabric handle (Gacén, Cayuela, Maillo, & Gacén, 2002). The purpose of the heat-setting is stabilization of fiber dimensions, relaxation of internal stresses in the fiber and stabilization of the crystalline structure (Bunsell 2009). Furthermore, researchers have proposed some studies regarding shrinkage control other than heat setting. In fact, they support the theory that open or loose construction fabrics show better crease recovery than dense fabrics (Karmakar, 1999). Fabric bulk depends on the loop length in all states of relaxation and also has a linear relationship with the tightness factor after full relaxation as well (Sharma, Ghosh, & Gupta, 1985) and thickness of fabric values also varies with respect to loop length (Prakask, 2008; Prakash & Thangamani, 2010). Some studies stated that loop length is the only factor influencing the dimensional properties of the knitted fabric (Matich-Leigh, Goswami, & Parachuru, 1993). (Marmarali, 2003) investigated that as the amount of spandex increases loop length values remain nearly the same; furthermore, the course and wale spacing values decrease.