Interference-Based Chromatic Coatings by Ion Plating Plasma Assisted Deposition Technology

The goal of replacing widespread and inexpensive galvanic treatments with suitable vacuum deposition techniques, in order to eliminate the environmental hazards and their polluting effects, is becoming, in some cases, more tangible. Shorter cleaning cycles, shorter pump-down times, reduced heating times of substrates and higher deposition rates allow the costs of new plasma-assisted processes to become competitive with respect to galvanic ones. Moreover, vacuum treatments offer superior mechanical and optical properties and non-conductive substrates (like glass, ceramics, plastics) can be more easily coated. This work describes the results obtained with Ion Plating Plasma Assisted deposition processes, using thermal sources, to realise special decorative chromatic effects with multilayer interferential thin films. Special attention was dedicated to the study of mechanical properties of the deposited layers in relation to the energy of condensing particles and bombarding ions, and to the measurement of their chromatic characteristics. Finally, some considerations about the practical applications of the described processes are presented.