Method for producing extrusion-coated laminates

A process for forming extrusion-coated laminates, which comprises the steps of:

• passing a substrate film between a roller gap formed by a cooling roller and a contact roller, wherein the roller gap has a narrowest point;
• forming a thermoplastic coating film having a surface part from a nozzle lip of an extruder nozzle and directing the lip toward the roller gap for causing the coating film to enter the roller gap;
• joining the coating film to the substrate film in the roller gap;
• providing a corona treatment station including two pin electrodes wherein between the electrodes a corona discharge burns, wherein the electrodes are comprised of a discharge electrode and a counter-electrode both located on one side of the coating film to provide a corona treatment on the coating film for promoting adhesion of the coating film to the substrate;
• disposing the corona treatment station in a region between the extruder nozzle lip and the narrowest point of the roller gap at a slight distance from the coating film, wherein the station is positioned closer to the narrowest point than to the nozzle lip;
• and
• subjecting the surface part of the extruded coating film to a corona discharge treatment from the corona treatment station while the coating film is at least partly in a molten state.