Thermoplastic filament crimping process - uses heated jet to deliver filaments to impact surface for heating followed by fast cooling

摘要

Process and appts. to crimp and cool thermoplastic yarns, which can be formed by a thermal treatment, particularly for filaments and/or split threads in which a jet delivers a heated airstream along the filaments as they are delivered, the filaments having been preheated, so that they are forced at high speed and/or high pressure against a surface. The filament material then passes through successive heating stages, followed by a high speed and/or high pressure cooling stage to fix the internal spring tension of the filaments. The process allows the softened filament material to take up a new structural character which can then be frozen, the treated filament having a high stretch strength, elasticity and stability in the crimpling.