Patent ID: 7891861

Claim:
A mixing method of mixing liquid additive with polymer dope by flow of said liquid additive through a supply conduit in feeding of said polymer dope through a flow line, said polymer dope being constituted by polymer and solvent, said mixing method comprising steps of: spreading said liquid additive in a transverse direction of a flow passage in said flow line through a distribution channel of said supply conduit, to eject said liquid additive to said polymer dope in said flow line, said distribution channel having a flat shape; directing said polymer dope in a ring shape after addition of said liquid additive by use of a hub shaped with a decreasing diameter; and after said directing step, collecting said polymer dope in a position downstream from said hub; directing said polymer dope from said collecting step in a ring shape by use of a second hub shaped with a decreasing diameter; rotating said second hub about an axis extending in said flow direction by electromagnetic induction, to cause said polymer dope and said liquid additive to flow finely.