Thermal roller imprint on surface of Teflon perfluoroalkoxy inlet tube

Abstract

The authors succeeded in transferring patterns from a plate mold onto a cylindrical surface of a plastic tube by thermal imprinting. A roller imprint technology was selected as a pattern transfer method. A cylindrical molding material was rolled on the surface of a plate mold under an optimized contact force and heating temperature. A Teflon perfluoroalkoxy (PFA) inlet tube with an outer diameter of 1∕16in. was selected as a cylindrical molding material. This tube is often used in connecting the microfluid devices in the studies of high performance liquid chromatography. A plate mold was fabricated by employing microelectromechanical systems and Ni electroforming technologies. The minimum linewidth and depth of an electroformed-Ni mold were 5 and 2μm, respectively. Several patterns were designed to mimic microcoil and comb actuator. A Teflon-PFA inlet tube was sandwiched between an electroformed-Ni plate mold set at the bottom loading stage and a buffer material sheet mounted at the upper loading stage of an imprinting system. After applying a right amount of heat to the electroformed-Ni mold, it was moved horizontally, resulting in the rolling of the tube against the patterned surface of the mold. Using this method, three-dimensional roller imprinting was executed. A relationship among the press depth, contact force, rotation speed of a Teflon-PFA inlet tube, and the imprinted depth was investigated. As a result, it was shown that optimization of the press depth was necessary in order to avoid any slippage or stalking, impeding the rotation of the cylindrical tube.