Dies for coextrusion of continuous and interrupted laminating resins - to obtain patterned laminates in a single pass

摘要

Extrusion dies for coextrusion of >=2 superimposed layers (a,b) of melt and partially or temporarily extracting the flow of one (a) of the layers prior to an outlet die zone which maintains the same profile thickness as the channel upstream from the obstruction. Used for producing decorative extrudates using contrasting materials, esp. where the interrupted layer is relatively thin. Process involves fewer operations than lamination of prefabricated films or patches, avoids risk of air entrapment between layers.