Extrusion die for multi core composite - filaments offers stable long-run operation

摘要

Die for forming composite filaments has several cores of one filament material dispensed in a matrix of a second material. The core streams discharge into a chamber which converges at an angle Theta of =75 degrees and which is fed with an annular and pref. also an axial stream of the matrix material. Pref. subsidiary passages sheath each core sub-filament in matrix material (co-axial or eccentric). For preparation of multi-core filaments or for manufacture of very fine filaments by subsequently removing the matrix material. Die design maintains stable core and matrix patterns throughout long prodn. runs - the flow path of the core filament streams is almost linear to avoid material hang-up and degradation. Sheathing of each core stream by matrix material avoids internal coalescence of the core streams.