| 摘要 |
PROBLEM TO BE SOLVED: To obtain high heat resistance, oil resistance and flame-retardant and to obtain excellent resistance to sulfuric acid by forming a coating layer consisting of polyamide resin and vinylidene fluoride series resin on the outside of a plastic optical fiber bare wire. SOLUTION: The plastic optical fiber bare wire 4 is formed by a core 1 consisting of polymethyl methacrylate series resin and a sheath layer 2 consisting of transparent fluorine resin surrounding the core 1 and with a refractive index lower than the core 1. An inner coating layer 6 consisting of the polyamide resin and an outer coating layer 7 consisting of the vinylidene fluoride series resin containing a vinylidene fluoride structure unit of 70 weight % or above are formed on the outside of this plastic optical fiber bare wire 4. The vinylidene fluoride series resin is stuck tightly to the sheath layer 2 of the bare wire 4 to be integrated, and the matter that the resin is peeled or shifted due to a wire stopper, etc., is eliminated. The size of the core 1 is formed to 900-1050μm, the thickness of the inner coating layer 6 is formed to 300-625μm and the thickness of the outer coating layer 7 is formed to 50-275μm. |
