A hydrophilie coating is applied to the surface of a substrate by a method which comprises the steps of (a) applying a first coating comprising a polyvinyl chloride copolymer; and (b) applying a second coating comprising a mixture of a poly(N- vinyl lactam), a polyvinyl chloride copolymer and optionally a zwitterionic compound. Preferably the polyvinyl chloride copolymer is a vinyl chloride-vinyl acetate copolymer. A substrate resulting from the method and a kit for carrying out the method are also provided.