| 摘要 |
PURPOSE:To prevent the deterioration in transmission loss due to microvoids, dust and impurities by using styrene-base resin obts. by bulk polymn. in the absence of oxygen in a tightly closed system as a core component. CONSTITUTION:A styrene monomer contg. a chain transfer agent or the agent and a polumn. initiator is bulk-polymerized at a temp. above the glass transition temp. in the absence of oxygen in a tightly sealed system to obtain >50mol% styrene polymer contg. trasition metallic ions such as <=50ppb Fe and Mn, <=10ppb Cu and Ni, and <=5ppb Cr and Co. Dust in said monomer is required to be <=20 pieces per 10cm optical path length at an arbitrary place in the monomer when the monomer is irradiated with an He-Ne laser beam of 632.8nm wavelength and obserbed. The polymer is used as the core component of an optical fiber, and EVA resin or other resin with superior adhesive strength at the core-sheath interface is used as the sheath component. |
