PRODUCTION METHOD OF OPTICAL FIBER CORE WIRE

• Main Authors: KASAHARA MINORU, YABE MASAHIRO, ISHIZUKI KUNIAKI, IWAYA MITSUHIRO
• Format: Patent
• Language: English; Japanese
• Published: 09.08.2022
• Subjects: CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUSENAMELS; CHEMISTRY; GLASS; JOINING GLASS TO GLASS OR OTHER MATERIALS; METALLURGY; MINERAL OR SLAG WOOL; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS,MINERALS OR SLAGS; SURFACE TREATMENT OF GLASS

To provide a production method of an optical fiber, capable of sufficiently suppressing curing of a primary layer and effectively avoiding micro-bend loss when further ultraviolet rays are irradiated with after production.SOLUTION: A production method of an optical fiber includes: a step of drawing an optical fiber bare wire from a fiber preform; a step of applying a first ultraviolet-curable resin to the periphery of the optical fiber bare wire; a first irradiation step of irradiating the first ultraviolet-curable resin with ultraviolet rays in an atmosphere whose oxygen concentration is higher than 2%; a step of applying a second ultraviolet-curable resin to the periphery of the first ultraviolet-curable resin; a second irradiation step of irradiating the second ultraviolet-curable resin with ultraviolet rays; and a third irradiation step of irradiating the first ultraviolet-curable resin and the second ultraviolet-curable resin with ultraviolet rays after the second irradiation step.SELECTED DRAWING: Figure 3 【課題】製造後に更なる紫外線が照射される場合に、プライマリ層の硬化を十分に抑制し、マイクロベンドロスを効果的に回避することができる光ファイバ製造方法を提供すること。【解決手段】ファイバ母材から光ファイバ裸線を線引きする工程と、前記光ファイバ裸線の周囲に第１紫外線硬化型樹脂を塗布する工程と、酸素濃度が２％よりも高い雰囲気で前記第１紫外線硬化型樹脂に紫外線を照射する第１照射工程と、前記第１紫外線硬化型樹脂の周囲に第２紫外線硬化型樹脂を塗布する工程と、前記第２紫外線硬化型樹脂に紫外線を照射する第２照射工程と、前記第２照射工程の後に、前記第１紫外線硬化型樹脂および前記第２紫外線硬化型樹脂に紫外線を照射する第３照射工程と、を備えることを特徴とする光ファイバの製造方法。【選択図】図３