METHOD FOR PRODUCING A COLOURED THERMOPLASTIC PLASTIC FILM, FILM AND USE THEREOF

摘要

The invention relates to a method for producing a coloured thermoplastic plastic film. According to said method, the thermoplastic plastic is melted and transported in an extrusion installation comprising an extruder, an extrusion nozzle with a wide-slot outlet and a chill roll which is fixed to a roll frame, and then leaves the outlet of the extrusion nozzle in the form of a flat, coloured melted web. Said coloured melted web is then applied to the chill roll and is cooled. The invention is characterised in that the chill roll has a rotational accuracy of +/- 10 µm or less and that the average distance between the outlet of the extrusion nozzle and the chill roll does not vary by more than +/- 25 µm during operation. The invention also relates to the coloured film of this type and to the uses thereof as a coloured film for a data carrier.