Producing polyurethane fibers for emission of light over surface of fibers, comprises producing fibers from basic material of polyurethane by extruding, and cooling extruded fibers in cooling zones and then subjecting to stretching process

摘要

The method comprises producing fibers from a basic material of polyurethane by extruding, where the basic material has residual moisture of below 0.02% before extrusion, adjusting the temperature and mass pressure of the extrusion on three positions along an extrusion cylinder, and cooling the extruded fibers in several cooling zones (30, 40) and then subjecting to a stretching process. The temperature adjusted along the cylinder lies between a glass transition temperature and a melting point of an extruding material and the highest value of the temperature is adjusted in an entrance area. The method comprises producing fibers from a basic material of polyurethane by extruding, where the basic material has residual moisture of below 0.02% before extrusion, adjusting the temperature and mass pressure of the extrusion on three positions along an extrusion cylinder, and cooling the extruded fibers in several cooling zones (30, 40) and then subjecting to a stretching process. The temperature adjusted along the cylinder lies between a glass transition temperature and a melting point of an extruding material and the highest value of the temperature is adjusted in an entrance area of an extruder screw. The mass temperature of the extruding material is as in the range of its melting temperature but not deviates more than 40 K from the melting temperature. The extruded fibers are cooled in a first cooling zone with a cooling media temperature below the glass transition temperature, and are cooled in the first cooling zone with an inlet temperature of highly 40 K below the melting temperature not under the glass transition temperature. The extruded fibers are cooled in a second cooling zone in a second medium with a cooling media temperature below the glass transition temperature. The extruded fibers are cooled up to below the glass transition temperature. The adjustment of the extruded fiber is carried out by stretching the fiber in the progression of the first cooling step at a temperature of the fiber above the glass transition temperature. The optical characteristics of the fiber are determined by the specific mass output of the extruder (20), are adjusted by different cylinder zone temperatures and are adjusted by the stretching process. An independent claim is included for a device for producing polyurethane fibers for the emission of light over a surface of the fibers.