Abstract: Disclosed and claimed herein are radiation curable compositions for coating an optical fiber containing an oligomer, a diluent, a photoinitiator, and optionally, additives. The oligomer includes a reactive urethane oligomer having at least three arms, each arm having a most distal termination point and bound together at a single junction point, wherein at least one arm comprises the reaction product of a polyol, a polyisocyanate, and an isocyanate-reactive (meth)acrylate. The reactive urethane oligomer possesses specified molecular weight and/or average functionality values, and it may possess specified chain length values between the oligomer junction point and the distal termination point along one or more arm(s). Also disclosed are methods of coating an optical fiber incorporating the compositions described herein, along with the coated optical fibers and cables produced therefrom.

Abstract: Disclosed and claimed herein are radiation curable compositions for coating an optical fiber containing an oligomer, a diluent, a photoinitiator, and optionally, additives. The oligomer includes a reactive urethane oligomer having at least three arms, each arm having a most distal termination point and bound together at a single junction point, wherein at least one arm comprises the reaction product of a polyol, a polyisocyanate, and an isocyanate-reactive (meth)acrylate. The reactive urethane oligomer possesses specified molecular weight and/or average functionality values, and it may possess specified chain length values between the oligomer junction point and the distal termination point along one or more arm(s). Also disclosed are methods of coating an optical fiber incorporating the compositions described herein, along with the coated optical fibers and cables produced therefrom.