Beskyttende materialer til optiske fibre, som i al væsentligt ikke misfarves

Radiation-curable compositions are disclosed which, after cure, are substantially non-yellowing. The compositions are particularly tailored for coating and bundling of optical fibers. A first preferred composition is based on a polyether-type of oligomer diluted with reactive diluents. Isocyanurate structures are included in the composition to raise Tg. A second preferred composition is based on fatty oil comprising (meth)acrylate groups and bisphenol A derivatives comprising (meth)acrylate groups. Photoinitiators can be included to increase cure speed. The formulations do not include material amounts of ingredients which tend to cause yellowing or, in theory, extended conjugation in the cured compositions.