Abstract: The invention relates to a process for production of a copper clad, electrically insulated base for printed circuit boards, wherein a foil, of copper, copper alloy, aluminum or aluminum alloy by electroplating on preferably both sides furnished with a 1-35 .mu.m thick unpatterned layer of copper or copper alloy, is under heat and pressure laminated with the copper surfaces facing an electrically insulating, resin containing base. The copper layers are electroplated onto the foil in such a way that the layers after lamination strongly adhere to the insulating base and at the same time exhibit a very poor adhesion to the foil, which easily can be stripped from the copper layers without splitting these. The foil works during the lamination as a mold plate, whereby conventional mold plates can be excluded. The invention also comprises the use of such a copper clad foil as a combined mold plate and base for the copper layers during the lamination.