US Patent 7285727 Flexible wiring boards for double-side connection

A flexible wiring board for double side connection is capable of improving the reliability of connection to circuit boards and a manufacturing process thereof. The flexible wiring board for double-side connection includes a polyimide film having a through-hole at a given location and first and second electrodes, one of which is provided on each side of the polyimide film. The second electrode closes one end of the through-hole in the polyimide film, such that any anisotropic adhesive used to connect an electric component to the first electrode will not flow through the through-hole to the other side of the polyimide film. The first and second electrodes are electrically connected each other by a plating layer.