Abstract: Chemically treated fibers of glass, carbon or polyamide have a treatment incorporating a copolymer or terpolymer with (vinylpyrrolidone-acrylate or acrylic moieties. In addition the treatment can have at least one film forming polymer, at least one organic/inorganic coupling agent, at least one fiber lubricant and water all in effective amounts to perform their stated functions. In one aspect of the invention the fibers are glass fibers which have a chemical treatment which is a dried residue of an aqueous chemical treating composition comprising at least one epoxy polymer, emulsion or dispersion in a predominant amount on a nonaqueous basis of the dried components amount of the aqueous chemical treating composition, at least one amino organofunctional silane coupling agent in an effective coupling agent amount, at least one cationic fiber lubricant in an effective lubricating amount and water. In this aspect the ratio of the epoxy to copolymer should be less than around 60 to 1.