Fabrication of dual-side metal patterns onto textile substrates for wearable electronics by combining wax-dot printing with electroless plating

Textile wearable electronics offer the consolidated advantages of both electronics and textile characteristics. Wearable electronic systems typically require conductive tracks as a platform to integrate electronic components. Herein we developed a site-selective electroless plating process to construct dual-side Cu patterns onto textile substrates. The proposed craft was mainly comprised of four procedures, namely, 3-aminopropyltrimethoxysilane (APTMS)-modification, wax-pattern printing, selective Au-seeding and Cu-pattern deposition. Specifically, waxes were transferred from commercial wax impregnated papers to APTMS modified fabrics with the aid of a conventional stylus printer. Intensive waxed dots then composed a wax pattern which corresponded to the input image designed on the computer. The wax pattern acted as a hydrophobic mask on the fabric surface and hindered the covered areas from being activated by subsequent Au catalysts. The non-covered areas, in contrast, were APTMS naked surfaces which normally adsorbed Au nanoparticles and had Cu tracks grown. The minimum width of the Cu track was 400 mu m with 3.57% deviation and the typical resistivity was 7.52.0 mu Omega cm, which was about 4.6 times that of the bulk metal Cu (at room temperature). The reliabilities of textile-based conductive Cu patterns were confirmed by air-exposure, ultrasonic washing and Scotch (R)-tape tests. In addition, the universality and versatility of the proposed method were validated by fabricating different metal patterns on various types of flexible substrates.