Thermal-electronic behaviors investigation of knitted heating fabrics based on silver plating compound yarns

Abstract

In this paper, three kinds of knitted heating fabrics (KHFs) were designed and fabricated by using silver plating compound yarns (SPCYs) and polyester staple fiber spun yarns (PSFSYs), and thermo-electric properties of KHFs and SPCYs were investigated by performing a series of experiments. Experimental results showed, with increasing ageing time and ageing temperature, the breaking strength of PSFSYs and SPCYs had nearly not changed, but resistances of SPCYs increased markedly. After performing 264 hours ageing at 120 C environment temperature, resistances of SPCYs exceeded the measuring range of the multi-meter. By taking and analyzing infrared temperature images of KHFs and SPCYs, strong linear correlation can be observed between surface maximum equilibrium temperature (SMET) of KHFs and SPCYs and power consumption density. Furthermore, strong linear positive correlation is between power consumption density of KHFs and inner equilibrium temperature of mimetic clothing. KHFs will have wide application prospect in active warming field because of a lot of advantages, such as an even surface temperature field in the heating process, structure simplicity, flexibility, etc.Keywords active warming, silver plating compound yarn, thermal performance, knitted heating fabric, infrared temperature image With the technological progress and innovation in materials and electronics fields, smart garments will become lighter and have more functions. Smart garments can acquire important information from the environment and human body and respond quickly to protect the human body against hot, cold and other injuries. 1-3 Axisa et al. 4 reviewed some smart systems with noninvasive sensors which may be smart, flexible, wearable, and inconspicuous: these systems can construct communication between patient and specialist to provide the best health services. Personal heating garments are another type of smart garment: Wang et al. 5 reviewed the advantages and disadvantages of personal heating garments, and pointed out that the uncontrolled temperature is the vital disadvantage for chemical heating garments; however, electrical heating garments (EHGs) with precise temperature-controlled units and flexible heating elements are expected to have a promising future. Many researchers have focused on heating fabrics and EHGs, and they not only developed all kinds of heating fabrics and EHGs, but also investigated their thermo-mechanical properties and thermal comfort. Hewitt 6 fabricated a flexible electric heating pad by using resistance wire and a flexible fabric support as early as 1929. Cottet et al. 7 presented the extensive characterization of textile transmission lines for use in wearable computing applications, and constructed a model of conductive textiles, and concluded that textile transmission lines can be used for frequencies up to

Properties of Surface Heating Textile for Functional Warm Clothing Based on a Composite Heating Element with a Positive Temperature Coefficient

“…A thermoplastic polyurethane (TPU) film (thickness = 150 µm; Ceylon 3095) was applied on top of the prepared SHE fabric via thermal transfer (165 • C for 15 s under a load of 10 kg) (Figure 4, step 2 ). Two sections of high-stretch fabric with the same dimensions were prepared separately, where TPU was also applied to one surface via thermal transfer (Figure 4, step 3 ). The two fabric sections were attached to the top and bottom of the SHE by thermally bonding the TPU-coated fabric surfaces (Figure 4, step 4 ).…”

“…The behavior of the PTC-SHT and NTC-SHT heating elements were compared based on the applied voltage, applied power, and heating temperature change under a constant voltage. 1 electrode patterning and screen printing, 2 TPU film bonding, 3 External textile preparation (TPU film bonding), 4 Bonding of inner and outer textiles.…”

“…Specifically, heated clothing has been previously developed for aerospace, combat suits, and other specialized applications. However, reductions in the costs associated with this technology have shifted the focus of research and development to heated clothing for everyday use [ 1 , 2 , 3 , 4 , 5 ]. This rise in popularity of heated clothing is attributed to its auxiliary functions for outdoor and daily life, and also for medical purposes such as promoting blood circulation and alleviation of muscle pain and arthritis.…”

“…Positive temperature coefficient surface heating textile (PTC-SHT) assembly conducted in four steps 1. electrode patterning and screen printing, 2 TPU film bonding,3 External textile preparation (TPU film bonding),4 Bonding of inner and outer textiles.…”

Advanced Functional Materials for Intelligent Thermoregulation in Personal Protective Equipment

“…Studying the behavior of a silver-coated polyester yarn embedded in three different knit structures showed that the maximum equilibrium surface temperature of heated knit fabrics is strongly correlated with the energy consumption density. Furthermore, the maximum equilibrium surface temperature can be influenced by the knitting method, as the electrical resistance of some structures seems to remain more stable than others during the heating process [164].…”