Metal plating onto the fibers using supercritical fluid (SCF) is a manufacturing technology used to make highly conductive fiber; further research is being carried out actively on synthetic fibers such as aramid, polyester and nylon fibers. However, metal plating onto the fibers using SCF has some problems. The adhesion between the fiber and plate metal is not high, and this method requires heat stability because of the high temperature and pressure under supercritical state, so natural fibers are of limited use. This paper investigated Lyocell fiber, which is cellulose fiber and has good heat stability, to find the optimum condition of the supercritical pretreatment. After making conductive fibers, abrasion and washing tests were carried out to examine adhesion between the fiber and plated metal. Also, to improve the adhesion between the fiber and metal much more, an attempt has been made to change the surface modification of the fiber by oxygen plasma, acid or base. In particular, the copper-plated conductive fiber after plasma treatment had high conductive properties, even after abrasion and washing tests were conducted.

The supercritical fluid method was used to copper-plate poly(ethylene terephthalate) fibers. First, selected Pd-complexes were impregnated into the fibers and free Pd metal was decomposed in the fibers by heat reduction. Using precipitated Pd, electroless copper plating was successfully performed. Poly(ethylene terephthalate) fibers having different shapes of cross section were investigated to improve the adhesion property of the copper plated on the fibers. The fibers having peanut shape of cross section had higher conductive properties than the other fibers having triangle or circular cross section, even after abrasion and washing tests. To improve adhesion between fiber and plated metal much more, an attempt has been done to change surface modification of fiber by UV or plasma. The copper plated fibers after treating surface modifications had higher conductivity than the non-treated fiber. Better adhesion property was obtained by these pretreatments.