| abstract |
In a coated optical fiber comprising a quartz glass fiber, a primary coating and a secondary coating, the secondary coating is formed by curing a resin composition comprising (A) 20-90 wt % of a polyurethane (meth)acrylate oligomer which is synthesized from an alicyclic polyisocyanate, contains 5-90 wt % of a polyurethane (meth)acrylate oligomer having a Mn of up to 1,000, and has an overall Mn of up to 10,000, and (B) 80-10 wt % of an ethylenically unsaturated compound, with electron beams accelerated at 50-125 kV. The coated optical fiber has a minimized transmission loss. |