CO-EXTRUSION DIE WITH RECTANGULAR FEED CHANNEL

摘要

A body member for an extrusion die for multilayer film has a passage-forming surface and an open feed channel formed in the passage-forming surface. The feed channel continuously decreases in depth from the feed channel inlet, and the feed channel is of substantially constant-width substantially rectangular cross-section along substantially its entire extent. Corners of the feed channel may be slightly rounded. Substantially constant-width feed channels of substantially rectangular cross-section may be used in blown film applications, in which case the feed channel extends in a spiral from the feed channel inlet, and in cast film applications, in which case the feed channel extends substantially linearly from the feed channel inlet. Dies can be assembled by arranging two body members with their respective passage-forming surfaces opposed to one another.

主权项

1. A body member for an extrusion die for multilayer film, wherein:
the body member has a passage-forming surface; the body member has at least one open feed channel formed in the passage-forming surface; each feed channel continuously decreases in depth from the feed channel inlet thereof; wherein each feed channel is of substantially constant-width substantially rectangular cross-section along substantially an entire extent of the respective feed channel.