Washable hydrophobic smart textiles and multi-material fibers for wireless communication

Abstract

This paper reports on the performance and environmental endurance of the recently presented wirelessly communicating smart textiles with integrated multi-material fiber antennas. Metal–glass–polymer fiber composites were fabricated using sub-1 mm hollow-core silica fibers and liquid state silver deposition technique. These fibers were then integrated into textiles in the form of center-fed dipole and loop antennas during standard weaving procedure. Fiber antennas performance was found to be directly comparable to classic ‘rigid’ solutions in terms of return loss, gain and radiation patterns, which allowed transmitting data through Bluetooth protocol at 2.4 GHz frequency. Applied superhydrophobic coatings (water contact angle = 152°, sliding angle = 6°) allow uninterrupted wireless communication of the textiles under direct water application even after multiple washing cycles.

Wearable solid-state capacitors based on two-dimensional material all-textile heterostructures

“…liver cells) after exposure to Cu nanoparticles was no more than 60% as assessed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide) assay (which is a method to assess cell metabolic activity). 23 In addition, the hydrophobic property of fabrics are highly common on technical textiles and would have significant role on protecting wearable electronics 24 and improve their washability, thus making it a requirement.…”

New Generation Wearable Antenna Based on Multimaterial Fiber for Wireless Communication and Real-Time Breath Detection

“…Textiles with integrated fiber antennas were tested under direct water application [61]. When the textile samples get wet, a shift of about 1.27 GHz of the operating frequency was observed, as revealed from the return loss measurements shown in (Figure 6a).…”

“…Textile featuring multimaterial fiber antenna covered with hydrophobic coating was first washed in 1 L of deionized water with 1 mL of a household detergent at 40 • C during 15 min using a heated magnetic stirring plate, then thoroughly rinsed in a hot tap water at 60 • C and dried by hot air (≈70 • C) flow [61]. The performances of the coated antenna were determined by measuring the return loss after 10 and 20 washing cycles.…”

Washability of e-textiles: current testing practices and the need for standardization

“…60,69,77,79,80,85 The average number of test cycles is lower than for the other clusters, which relates to the number of very long-running tests in which fewer cycles are conducted. Testing temperatures are highest when alternative methods are employed, with an average testing temperature of 47 C; in one-third of the cases the washing temperature is at or above 50 C. 78,81,82,84 The comparability of the alternative methods with actual wash cycles is not sufficiently researched. Only Tang et al 69 test their samples both by stirring in water and in a household washing machine, while Gaubert et al compare the household washing results for their conductive textiles with placing them in water with different types and amounts of detergent.…”

“…These methods include placing the samples in water or wash liquor (without further agitation) 60,[77][78][79][80][81] and stirring the samples in a beaker. 69,77,82,83 Others employ laboratory testing equipment, such as the previously mentioned dyeing unit Datacolor Ahiba, 84 or subject the samples to "continuous mechanical washing." 85 Lin et al wash their samples by hand in water without detergent present.…”