Polymerisable Resin Film

A resin film comprising a layer of polymerisable resin which is in the form of a solid layer at 20° C., at least 50 wt % of the polymerisable resin comprising at least one polymerisable vinyl ester prepolymer having at least two carbon-carbon unsaturated functional groups, the prepolymer being polymerisable by reaction of the unsaturated functional groups to form a cured resin, wherein the polymerisable resin further comprises a curing system for polymerizing the polymerisable vinyl ester prepolymer, wherein the at least one polymerisable vinyl ester prepolymer comprises at least one prepolymer which is present in a concentration of at least 10 wt %, based on the weight of the polymerisable resin, and has the structure R1n-R2-R1′m, wherein R1 and R1′ are the same or different, n and m are each at least one and may be the same or different, and each of R1 and R1′ includes a carbon-carbon unsaturation at a free end thereof remote from R2 and includes a residue of an epoxy resin, and wherein R2 is a polyfunctional chain extending linker between R1 and R1′, and is derived from a polyfunctional carboxylic acid having the structure R—Fnx, where Fn is a carboxylic acid functional group, x is at least 2, and R comprises an organic moiety having aliphatic, araliphatic, cycloaliphatic, heterocyclic and/or aromatic groups, containing any type and/or combination of saturated, unsaturated and/or aromatic carbon bonds, and wherein R may be unsubstituted or substituted by functional groups and/or heteroatoms.