Abstract: Disclosed is a photopolymerizable resin composition. The photopolymerizable resin composition includes 40 to 80% by weight of a photopolymerizable urethane (meth)acrylate oligomer, 10 to 40% by weight of a low-viscosity multifunctional urethane acrylate oligomer, and 1 to 10% by weight of a photoinitiator. The photopolymerizable resin composition is cured by UV light to form a film whose shrinkage and expansion rates after immersion in hot water are low, leading to minimal changes in tensile strength and adhesive strength before and after water immersion. Further disclosed is an optical fiber using the photopolymerizable resin composition. The optical fiber undergoes minimal change in strip force before and after immersion in hot water.

Abstract: Disclosed is a photocurable coating composition for an optical fiber. The photocurable coating composition can be used to produce an optical fiber having a low polarization mode dispersion (PMD) even by a non-spinning process. The photocurable coating composition includes a photopolymerizable urethane acrylate oligomer, a reactive monomer, a photoinitiator and an amine additive. Further disclosed is an optical fiber using the photocurable coating composition. The optical fiber has a polarization mode dispersion (PMD) of 0.1 ps/?km or less when produced by a non-spinning process.

Abstract: The present invention is directed to a photocurable and antistatic resin composition for coating an optical fiber, comprising (A) a photopolymerizable urethane acrylate oligomer, (B) a reactive monomer having at least one (meth)acrylate or vinyl group, (C) a photoinitiator, and (D) an antistatic agent compatible with the oligomer and monomer components, and optionally (E) a pigment or dye. The coating of the inventive composition can increase the productivity of the optical fiber, and provide an optical fiber having a uniform coating layer.

Abstract: The present invention is directed to a photocurable and antistatic resin composition for coating an optical fiber, comprising (A) a photopolymerizable urethane acrylate oligomer, (B) a reactive monomer having at least one (meth)acrylate or vinyl group, (C) a photoinitiator, and (D) an antistatic agent compatible with the oligomer and monomer components, and optionally (E) a pigment or dye. The coating of the inventive composition can increase the productivity of the optical fiber, and provide an optical fiber having a uniform coating layer.

Abstract: A UV-curable and foamable resin composition comprising a photopolymerizable urethane acrylate oligomer, a photopolymerable monomer, a photo polymerization initiator, a photolytic foaming agent selected from an azo compound, a combination of sulonium salt and an inorganic carbonate, and a mixture thereof, and a photolysis catalyst is useful for coating a fiber or ribbon bundle to be applied to an air blown fiber system.

Abstract: The present invention relates to a method for preparing a GI (graded index) plastic optical fiber preform having a radial refractive index gradient, the refractive index increasing gradually from the outer periphery of the preform toward the center thereof, comprising inserting a 1st plastic tube (inside diameter: d1i, outside diameter: d1o) (111) made of a first polymer (refractive index: n1) in a cylinder reactor (inside diameter: d0i, d1o?d0i) and inserting a 2nd plastic tube (inside diameter: d2i, outside diameter d2o, d2o?d1i) (112) made of a second polymer (refractive index: n2, n2?n1) in the 1st plastic tube, the reactor, the 1st and 2nd plastic tubes are positioned coaxially, injecting a precursor of a third polymer (refractive index: n?, n??n2) into the 2nd plastic tube, injecting a precursor of a fourth polymer (refractive index: n?, n1?n??n2) into the space between the 1st and 2nd plastic tubes.