Filters for polymer spinneret assemblies and their manufacture.

摘要

A spinneret assembly comprises a body having a perforate plate forming a spinneret at one end through which molten polymer is extruded to form filaments. The body contains a filter upstream of the plate. The filter is formed from a plurality of layers of metal filter media including at least one layer of fibre metal and at least one layer of a sintered particulate metal. This is particularly effective in removing gels in the molten polymer and has extended life. The layers of metal filter media are held in a sleeve with the downstream layer being welded to the sleeve around its periphery so that the cross-section of the sleeve is not reduced at this point.