OPTICAL FIBER AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To improve quality of a coating resin by sufficiently promoting photopolymerization of resin.SOLUTION: An optical fiber 1A comprises: a core 12; a clad 14 which covers the core 12; and an ultraviolet-curable coating resin film 20 which covers the clad 14. The coating resin film 20 includes a plurality of layers 22, 24, and 26. At least one layer of them is formed by curing a curable resin composition containing a photoinitiator and a photosensitizer. The lowest energy in an excited triplet state of the photosensitizer is about the same as the lowest energy in an excited triplet state of the photoinitiator or is higher than the lowest energy in the excited triplet state of the photoinitiator. An average molecular extinction coefficient of the photoinitiator for ultraviolet light having a wavelength of 350 to 400 nm is 160 (moldmcm) or more.