PRODUCTION OF PLASTIC OPTICAL FIBER

摘要

PURPOSE:To improve the transmission loss and the heat resistance by setting a drawing system and drawing conditions to specific ranges. CONSTITUTION:Polycarbonate melted by a melt extruder for the component of a fiber material layer is measured of weight by a gear pump and is then introduced to a composite spinning head part. The component of a sheath material layer is similarly melted by the melt extruder and is then introduced through the gear pump to the spinning head part. The fiber component and the sheath component introduced into the spinning head part are combined in a pack mouthpiece part and are discharged from a mouthpiece hole. The extrusion of the two-layered structure discharged in such a manner is cooled and is once taken up as undrawn yarn via godet rolls. The yarn is then so drawn as to satisfy equation I. The excellent transmission loss and heat resistance are obtd. in this way.