Coating process

The invention relates to a process for coating a material surface, comprising the steps of:(a) covalently binding a compound comprising an ethylenically unsaturated double bond to the material surface;(b) polymerizing a monomer comprising a reactive or crosslinkable group on the surface and thereby providing a primary polymer coating comprising reactive or crosslinkable groups,(c) in case of a monomer comprising a reactive group in step (b) reacting the reactive groups of the primary coating with a further compound comprising an ethylenically unsaturated double bond and graft-polymerizing a hydrophilic monomer and optionally a co-monomer having a crosslinkable group onto the primary coating obtained according to step (b) and(d) in case of crosslinkable groups being present in step (b) or (c) initiating crosslinking of said groups. The coated articles that are obtainable by the process of the invention have desirable characteristics regarding adherence to the substrate, durability, hydrophilicity, wettability, biocompatibility and permeability and are thus useful for the manufacture of biomedical articles such as ophthalmic devices.