| abstract |
A process for applying an adherent electrically insulative moisture-resistant composite coating to a substrate. A thin, adherent, highly cross-linked, substantially liquid moisture-impervious primer coating is provided on the substrate by glow discharge polymerization of a low molecular weight hydrocarbon monomer in a low pressure chamber containing the substrate, the monomer being selected from among methane, ethane, propane, ethylene, and propylene. A second polymeric coating layer is provided over the primer coating by glow discharge polymerization of a second precursor comprising a hydrocarbon or substituted hydrocarbon. The precurser exhibits a hydrogen yield of not greater than about 0.75 hydrogen atoms per molecule under the glow discharge polymerization conditions under which the second layer is deposited, whereby the second polymeric coating layer is substantially resilient and strongly bonded to the primer coating and the second layer comprises a high concentration of surface and bulk free radicals. An article produced by the process and an apparatus for carrying out the process are also disclosed. |