Device for producing multilayer blown film

摘要

A method for producing multilayer films by the blown film method includes of producing a nine-layer film by combining at least two melt streams and at most three melt streams at each of plural combining locations in a blowing head. The coextrusion blowing head includes a base plate and ten concentric rings defining nine melt channels for the nine individual melt streams. At least two of the concentric rings are supporting rings including flanged attachments for respectively receiving at least one other of the rings. The supporting rings are arranged directly on the base plate.