| abstract |
An optical fiber coating material comprising (A) 100 parts by weight of a polyether polyurethane bearing at least two ethylenically unsaturated groups with a Mn of 800-10,000, and (B) 1-40 parts by weight of a nitrogenous reactive diluent is cured by irradiating thereto electron beams, produced by driving electrons under an accelerating voltage of 50-190 kV, in a dose of 10-100 kGy. The method succeeds in effectively curing the optical fiber coating material into a cured coating having stable properties. |