Utilization of bicomponent melt spinning process for the preparation of fibers with optical functionality

摘要

Various fundamental researches conducted to introduce optical functionality to the synthetic fibers through the utilization of bicmponent melt spinning process will be presented. A new technology to generate granular structure on the surface of polyamide/polyester blend fibers was developed. This technology is applicable for the development of artificial hair of aesthetic appearance. Continuous fabrication of the graded-index plastic optical fibers was attempted applying the sheath-core bicomponent spinning process. Enhancement of the diffusion of low molar-mass additive of high refractive index in the fiber formation process was the key factor for the control of the refractive index distribution in the fiber cross-section. High controllability of molecular orientation in the high-speed melt spinning process of bicomponent spinning was utilized to prepare the fibers applicable for the production of reflective polarizing films (RPF). When refractive index in the direction perpendicular to the fiber axis of poly(ethylene naphthalate) and polystyrene components in the islands-in-the-sea type bicomponent fibers were matched whereas those parallel to the fiber axis showed significant difference, the prepared fiber with the diameter of 40 μm exhibited the reflectance of 60% for the light polarized parallel to the fiber axis whereas the transmittance was nearly 100 % for the light polarized perpendicular to the fiber axis.