| 摘要 |
The invention provides a reliable and productive method for the preparation of a double-sided flexible circuit board having two circuit patterns on the two surfaces of a flexible base film in which the two circuit patterns are electrically connected through an opening penetrating the base film. Different from conventional methods in which the electrical connection between two circuit patterns is obtained by filling the opening with an electroconductive paste, the electrical connection in the invention is obtained by (a) forming a first circuit pattern on one surface with a conductive paste which is then brought into a semi-cured condition, (b) punching the conductive layer and the base film with a needle to make an opening whereby the conductive layer is plastically deformed and protruded on the opposite surface through the opening and (c) providing the opposite surface with the second circuit pattern by printing so that the layer of the second circuit pattern can be in contact with the protruded portion of the first conductive layer. |
