| abstract |
A process for providing a protective coating on a substrate comprises (1) applying to the substrate a coating composition comprising a homogenous mixture comprising an inorganic sol and polymerisable organic species, the inorganic sol being obtainable by hydrolysing hydrolysable inorganic monomer precursors to form inorganic monomers; (2) polymerising the polymerisable organic species; and (3) polymerising the inorganic monomers, wherein polymerisation of the organic monomers is initiated prior to completion of polymerisation of the inorganic monomers, to form a solid coating on the substrate. The resulting coating comprises interpenetrating inorganic and organic polymer networks, and may be formulated to be transparent. It is useful in the protection of a wide variety of substrates, and in particular for providing scratch/abrasion resistance to low melting point plastics materials such as polycarbonates and polyacrylates. |