Fibre-reinforced two-component resin system based on vinyl ester

Reinforcement material fibers and peroxide composition containing resin systems two components, comprising at least a first component (A) resin having a low acid, containing one or more groups with ethylenic unsaturation and one or more isocyanate-reactive groups and optionally also containing at least monomer reactive in said first resin component and a second component (B) resin consisting of a polyisocyanate compound having an isocyanate functionality of at least 1, 75, characterized in that: - the first and second components (a) and (B) resin is present in an unreacted form, - wherein the first component (a) resin is selected from the group of resin components that have one or more groups with ethylenic unsaturation and one or more isocyanate-reactive groups, and this first resin component is chosen from the group of vinyl ester resins (A1a), - the material of fiber reinforcement is provided with reactive sites isocyanates, and - the molar ratio of isocyanate groups in the second component (B) resin versus isocyanate-reactive groups in the first component (a) resin is in the range 0.01 to 0.55.