Process and spinning device for making microfilaments

In a process for producing microfilaments that are useful in the production of textile or spun bond fabrics having a silk-like character comprising:

• (a) melt extruding a molten melt-spinnable polymeric material downwardly through a plurality extrusion orifices,
• (b) passing the resulting molten melt-spinnable polymeric material in the direction of its length through a solidification zone having an entrance end and an exit end wherein cooling air is transversely blown in contact with said molten polymeric material and it is transformed into a solidified microfilamentary material of less than 1 dtex per filament, and
• (c) exerting a pulling force on said solidified microfilamentary material after it leaves the exit end of said solidification zone so as to accomplish substantial drawing of said molten melt-spinnable polymeric material intermediate said extrusion orifices and its transformation into a microfilamentary material of less than 1 dtex per filament;
• the improvement comprising surrounding said resulting molten melt-spinnable polymeric material as it passes from said extrusion orifices to the entrance end of said solidification zone with a protective stream of heated air that flows parallel to the direction of movement of said molten polymeric material and blowing said cooling air transversely in contact with said molten polymeric material in step (b) at a distance of at least approximately 100 mm, below said extrusion orifices.