Patent ID: 8747725

Claim:
A method of producing with a blow head a multilayer blown film having at least two plastic layers, comprising the steps of: feeding a melt to at least two individual gaps, with each of the individual gaps guiding an individual stream of the melt, and the individual streams each forming individual layers of the film, with at least one of the gaps that guide the individual stream having a melt distribution zone in which a melt feed line extends into the individual gap in a peripheral direction (φ) of the blow head; transferring the melt into a flat form in the at least two individual gaps; combining of the individual streams in a common annular gap; and influencing a temperature of at least one peripheral section of at least one of the individual streams after leaving an extruder and before reaching the annular gap with at least one of a plurality of thermocouples, with the thermocouples being arranged on or in a component which borders the individual gap and lies at least partially at a level of the individual gap in the direction of the melt stream, a thickness of at least one of the individual layers of extruded film and at least one sector that forms a partial area of a periphery of the blown film being controlled with the at least one thermocouple, with at least two of the thermocouples being assigned to different sectors that form the partial area of the periphery of the blown film, and with the at least two thermocouples assigned to the different sectors being controlled individually.