| 摘要 |
A die head (10) for extruding a chemical additive comprises an interior channel (25) for receiving the chemical additive and a pair of mutually opposite discharge lips (21, 22) forming at least one discharge mouth (20) therebetween, which discharge mouth (20) is in fluid communication with the interior channel (25). At least one of the discharge lips (21, 22) is movable relative to the other in a direction substantially parallel to the movement of the chemical additive through the discharge mouth (20). By reciprocally moving the discharge lip (21), one can remove contamination build-up in the discharge mouth (20). |
