| abstract |
An optical fiber (AGF) capable of maintaining good reliability by suppressing the occurrence of cracks due to migration of a plasticizer even when exposed to a high temperature environment. A core 11 made of glass, a clad 12 made of glass covering the outer periphery of the core 11, and a polymer coating 13 covering the outer periphery of the cladding 12, and the polymer coating 13 having a Young's modulus at 23 ° C .: An optical fiber 20 having characteristics of 30 to 700 MPa, glass transition temperature (Tg): 30 to 90 ° C., and crosslinking density at 120 ° C .: 0.1 to 3.0 mmol / cm 3 . Based on the total weight of the polymer, at least one oligomer selected from epoxy (meth) acrylate and urethane (meth) acrylate: 30 to 90% by weight; unsaturated group-containing monomer: 5 to 65% by weight; and light An optical fiber coated with a cured product of an ultraviolet curable resin composition containing a polymerization initiator: 0.1 to 10% by weight. [Selection] Figure 2 |