Patent ID: 11932716
Assignee: COVESTRO (NETHERLANDS) B.V.
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C  G | IPC C  G

Claim 0:
1. A radiation-curable resin composition for formation of a primary covering layer of an optical fiber, comprising a urethane oligomer with an ethylenic unsaturated group, a free-radically polymerizable non-urethane monomer and a polymerization initiator, wherein
the urethane oligomer with an ethylenic unsaturated group is the reaction product of a polyether-based urethane prepolymer and an isocyanate reactive compound containing one active hydrogen group,
the isocyanate reactive compound contains an aliphatic alcohol and an ethylenic unsaturated group-containing isocyanate reactive compound,
the aliphatic alcohol content in the isocyanate reactive compound is 24 mol % or higher, and
the urethane oligomer with an ethylenic unsaturated group contains a monofunctional urethane (meth)acrylate oligomer and a bifunctional urethane (meth)acrylate oligomer wherein a ratio of the number of moles of the monofunctional urethane (meth)acrylate oligomer with respect to the number of moles of the bifunctional urethane (meth)acrylate oligomer is from 3/1 to 100/1.