Screen Printing Carbon Nanotubes Textiles Antennas for Smart Wearables

Abstract

Electronic textiles have become a dynamic research field in recent decades, attracting attention to smart wearables to develop and integrate electronic devices onto clothing. Combining traditional screen-printing techniques with novel nanocarbon-based inks offers seamless integration of flexible and conformal antenna patterns onto fabric substrates with a minimum weight penalty and haptic disruption. In this study, two different fabric-based antenna designs called PICA and LOOP were fabricated through a scalable screen-printing process by tuning the conductive ink formulations accompanied by cellulose nanocrystals. The printing process was controlled and monitored by revealing the relationship between the textiles’ nature and conducting nano-ink. The fabric prototypes were tested in dynamic environments mimicking complex real-life situations, such as being in proximity to a human body, and being affected by wrinkling, bending, and fabric care such as washing or ironing. Both computational and experimental on-and-off-body antenna gain results acknowledged the potential of tunable material systems complimenting traditional printing techniques for smart sensing technology as a plausible pathway for future wearables.

Screen Printing of Silver and Carbon Nanotube Composite Inks for Flexible and Reliable Organic Integrated Devices

“…As evident in Figure b, both inks reveal clear thixotropic behavior over time (time-dependent), and the recovery rate of the Ag/CNT composite ink at the leveling point (105 s) is higher than 80%, which is higher than that of the Ag ink (40.8%). This indicates that ink with a higher elasticity is useful for forming fine pattern fidelity. − …”

Damage Detection of CNT/CNC-reinforced Foam-cored Sandwich Composites by Acoustic Emission Tests under Flexural Load

“…For the effective dispersion of CNTs and CNCs, distilled water is proposed to be one of the most accessible and appropriate liquids. Considering the chemical structure of CNCs, they provide colloidal stability by bonding with distilled water thanks to their hydrophilic parts and their bonding ability with CNTs through nonpolar parts [11]. After vaporizing distilled water, polymeric foams could be reinforced with the optimum CNT/CNC powder concentration.…”

Wearable Antennas for Sensor Networks and IoT Applications: Evaluation of SAR and Biological Effects

“…Furthermore, in order to estimate the applicability of antennas for body-worn wireless devices, the antenna parameters and characteristics need to be studied both in free space and on the human body [ 4 ]. Several types of flexible wearable antennas for embedding into garments or accessories have been presented that fully or partially meet the design requirements: patch antennas [ 5 , 6 , 7 , 8 , 9 , 10 ], textile slotted waveguide antennas [ 11 ], monopole textile antennas [ 12 , 13 ], and fully-textile loop antennas [ 14 , 15 ]. The effects of the human body on antenna parameters and characteristics has been numerically investigated by employing homogenous (cylindrical [ 11 ], rectangular [ 11 , 14 ], forearm [ 5 ], full-scale human body model [ 7 ]) and multilayer (cylindrical [ 6 ], rectangular [ 15 ]) human body models.…”