The stability study of copper sputtered polyester fabrics in synthetic perspiration

Copper films with a thickness of 220 nm were deposited onto polyester fabrics by magnetron sputtering technology. To improve the stability of copper films in synthetic perspiration, the Cu-coated fabric was treated by a solution of Benzotriazole (BTA). Finishing agents with 0.1, 0.5, 1, 5, 10 g/L concentrations were applied on Cu-coated fabrics by a method of impregnation. The surface morphologies were observed by scanning electron microscopy (SEM). The electromagnetic interference shielding effectiveness (EMI-SE) and the electrical conductivity were measured to characterize the degree of damage to the copper film, respectively. In addition, the ultraviolet (UV) absorption of the fabrics treated with differ rent concentrations of BTA was investigated. The results show that the protective ability of BTA on copper film in synthetic perspiration improved with the increase of its concentration; and the copper film treated with the BTA concentration of 1 g/L presented good stability, which the sheet resistance value was 1.15 Ω/sq, and the average of EMI-SE value was 35 dB. However, when the BTA concentration is higher than 1 g/L, both the EMI-SE and conductivity were reduced. The BTA treatment improved the stability of Cu-coated fabrics in synthetic perspiration, which can help enlarge the application area of Cu-coated fabrics.